hello welcome to my channel my name is
Nico Carver I am a deep sky
astrophotographer and I share these
videos with you all to help beginners
who are interested in deep sky
astrophotography and with some tips that
I've learned along the way and I also
just like sort of sharing what I'm up to
and I'm a gearhead so I talk a lot about
the gear that I use and what it does and
we'll start with that today but the this
video actually came from a comment on
one of my other videos so I do look at
the comments and the comment was from
Patrick Hand who commented can you
create a video showing your workflow for
a basic capture of m42
I am new to DSO imaging okay so for
those of you who don't know m42
is Messier 42. Messier was an
astronomer that came up with a list of
things that were not comets but that
list is still being used today it's
mostly galaxies clusters and nebulae
like the one we're seeing right here
this is the Orion Nebula also known as
m42 we're actually seeing more than just
m42 here this little part right there is
m-43 and then in the picture that I'm
going to capture we'll also get the
Running Man Nebula anyways so the idea
basic idea with this video is start to
finish every step how do you make a DSO
image so it's going to be probably a
pretty long video I'm gonna start here
in the house explaining what equipment
that I'm going to use and why you know
I'm using this particular equipment I'm
using pretty beginner equipment and
today or tonight and then we'll go on to
setting up the equipment making sure we
know how it works then actually setting
it up you know in the location in a dark
sight
starting the capture process making sure
that we're at the right exposure level
everything looks good
capturing what we call our light frames
that's of the actual object so we're
gonna try to do maybe I don't know a
hundred 30-second exposures of m42 and
see what we get out of that and then
I'll show making the calibration frames
those are to help with certain kinds of
noise things like dark current and fixed
pattern noise on the sensor we'll get
more into that but they're basically the
darks the bias and the flat frames and
we're going to capture each of those and
I'll show you how then once we have all
of that data we'll take a look at it
what do these things look like in their
raw state and we'll move on to
processing now because we could go with
a bunch of different directions and
processing in this main video I'm going
to do deep sky stacker and Photoshop
deep sky stacker is free and Photoshop
is just really popular so I think a lot
of people might be interested in that
combination of programs then I'm gonna
have some other videos below this one
where it sort of branches out so you
could watch the first half of this video
everything about capture and then switch
to another processing video if you don't
use deep sky stacker in Photoshop I'll
have one video that goes into doing it
all in pix insight and then another
video that shows deep sky stacker + gimp
which is a free Photoshop alternative so
if you're a beginner and you don't want
to spend any money on software you can
watch that deep sky stacker + gimp video
to show what you could do with just free
software because this video is for
people who are new to DSO imaging I want
to start with a affordable gear here and
also not over complicate this video
because it could go on for hours if I
throw in everything auto guiding and
computer control and plate
solving and everything like that so I'm
just going to show basically using the
mount with the hand control using a
basic telescope and DSLR and that's it
no auto guiding nothing like that
short exposures on a bright target let's
break down the gear that we'll use
tonight we'll start with this this is
the mount I'm gonna use this is actually
just a mount head it goes on a tripod
but this is the part that actually does
the work it has the stepper motors
inside here and this is I have a video
unboxing this you can watch that if you
want to I've made a few little changes
to it I have an adapter so I can use my
qhy pole master for polar alignment it
changed out some of the knobs and added
some little waterproof velcro things
here to attach different things to it
but other than that it's pretty much
stock I'm gonna be using it just with
the hand controller tonight I'm not
gonna do computer control and I'm also
just going to be running it off if I can
get this open
double-a batteries so eight double a's
which is really nice because there's not
going to be any wires hanging off my
setup tonight it's been a long time
since I've had an ester photography
setup with no wires hanging off but this
is gonna be all running off internal
batteries including the mount so that's
gonna be really fun this accepts vixen
dovetail and I want to point out that it
might look like I'm endorsing this mount
I don't accept any endorsements from any
company I just I've bought this
personally the reason I bought it was
for travel because the case for this is
small enough that I can bring it
carry-on on an airplane that's the
reason I bought this mount it's not
necessarily the mount I would recommend
for a beginner amount if you're new to
deep sky astir photography the reason is
is it's not going to give you much room
to grow
you can't put much weight on it really
only like 10 pounds in under or maybe
nine pounds in under and it's not super
accurate it's not like a more you know
beefy equatorial mount like in our Ryan
Atlas which is my main one that I use
and so it's not going to give you those
results that you're gonna want as a
beginner and you're just going to be
fighting it too much so it's not really
what I'd recommend if you're new to this
I would save a little bit more buy used
do something to get a little bit bigger
mount but I'll try to do a review of
this soon because I think it would
really benefit people who want a travel
mount that is a full equatorial mount
can do go to can do guiding
theoretically still working on that and
so anyways enough said about this the
scope that I'm going to be using the
telescope is this one right here this is
the as you can see on the side there
Astrotech AT60 ED it's a doublet
design the nice thing about a doublet is
that they can stay pretty low weight
once you add and now you know the more
elements of glass that you add into a
telescope design the heavier it gets the
other nice thing about this scope is
like watch this
that's how small it gets so it's very
portable I can actually rack the focuser
in here you can see it gets quite small
speaking of the focuser this is the best
part of this mount all right I mean
telescope that this is the best part of
this telescope that it is 370 dollar
telescope but it actually comes with a
really nice two inch rack and pinion
focuser that has all that really works
it holds enough weight it has a scale
there on the side it's nice and smooth
it has the dual speed I haven't noticed
any backlash
so this focuser is rock-solid which is
rare to find on
cheap telescopes like this cheap is
relative of course speaking of cheap
telescopes you might be wondering well
why would I get something like this with
so little aperture win for 4 or $500 I
could instead buy like a fast Newtonian
like a six inch or an 8 inch Newtonian
it's a good question the learning curve
on a Newtonian is going to be much
steeper and you're probably gonna have
to make more upgrades I haven't found
any of those like $400 Newtonian to
actually have a good stock focuser so
you'd probably have to replace it so
that might double the cost and just you
would also need a much better amount
I've struggled with an 8 inch Newtonian
on my Orien Atlas you really want to
move up into like holas Mandie or
astrophysics mount probably to really
get good results so you're gonna need a
much better amount if you have all the
money in the world that might work for
you but if you're looking for something
cheap beginner wise this scope I would
recommend or like a 70 millimeter or 80
millimeter or factor would be fine too
but this one is nice and lightweight and
like I said three hundred and seventy
dollars there's a couple things I added
to it that brought up the total cost to
500 this first one is called the camera
angle adjuster and you basically loosen
a screw here and then this whole part
right here can now rotate and that's
really nice
for framing objects because a lot of
times just the stock rotation you know
with the camera level like this is not
gonna really work you don't really want
to have to like undo a bunch of threads
and everything to change the rotation of
the camera so having a little screw
right there that I can just loosen up
and then tighten back down when I got
the angle that I want is really nice
this I think was 30 or 40 dollars and
then behind that this is the Astrotech
8086 de d field flattener it
just a field flattener so a lot of times
you'll find flatteners also our reducers
meaning they change the focal length and
the speed this one doesn't do that it
just flattens the field so this
telescope stays at 360 millimeters focal
length but what a field flatter does is
normally with a refractor you'll notice
that if you're using a big chip like in
a DSLR the center of the field is nice
and flat meaning you have nice round
good stars but as you get closer to the
corners and the edges of your frame all
the stars start warping and they warp
out towards the corners so you'll see
that they have this pattern where
they're going out like this and these
bottom corners and out like this and the
top corners and to avoid that the only
one thing we can do is get a field
flattener for our telescope or by a
design like a quad where the flat inner
element is built into the telescope this
is $100 for imaging I think this is
probably essential the camera angle
adjuster is not quite as essential but I
would definitely get a field flattener
with this telescope and this is just a
forty eight millimeter t2 Canon adapter
and then oh and then a vixen plate this
did not come with the telescope you
could mount it other ways but I like the
vixen plate especially for most
equatorial mounts this is what you would
want these are really cheap though you
can get these basically anywhere even
used okay so that's the telescope it's
the again the Astrotech 80 60 IDI and
this hanging off the back of it here is
the camera that I'll use tonight this is
a Canon t6i it's not modified some
people modify their DSLRs they remove
certain low-pass filters and things that
are riding in front of the sensor to get
better each a sensitivity this one has
not been modified in any way so it's
stock I also have not put on
magic lantern firmware which is
something I would usually do because
Canon DSLRs do not have usually a
built-in intervalometer meaning a way to
take many exposures without touching the
camera so tonight I'll be using a newer
or newer just a cheap intervalometer you
can get on Amazon I'll put the link to
all this stuff on my website you just
plug this in and then you program how
many pictures you want to take and for
how long the delay between the pictures
is basically just if I set 30 second
pictures on the camera and then I say
take a picture every 35 seconds on here
then there would be a five-second delay
between each 30-second exposure the
reason you might want to program a
little delay in is because otherwise you
can get a little bit of a vibration
effect from the from the mirror closing
and showing all right so intervalometer
good easy thing to get about $20 if
you're not comfortable with putting
something like magic lantern on your
Canon camera speaking of the camera I'm
a Canon person I always have been but
for astrophotography Canon or Nikon
DSLRs work really well especially when
you're starting out why not
Sony or one of the other brands only
Canon and Nikon DSLRs since about 2011
or 12 have been consistent about not
altering the raw file we'll get more
into what or why you want RAW files when
we get into processing but basically you
for astrophotography your camera has to
be set to raw and you want just an
unadulterated raw file Sony and some of
the other brands have this problem
called star eater where the raw is
optimized for daytime use so they lower
the some there's some kind of noise
adjustment or something but when you do
that for astrophotography it kills a lot
of the dim stars and
just no good so canon or nikon DSLR are
definitely the most popular for a reason
they also have the most support if you
later on decide you want to hook this up
to a laptop there's something called
backyard yose or backyard Nikon that can
control the camera for you and then you
wouldn't need this anymore
okay so I said just mount scope camera
there's actually one more piece that you
would want with a setup like this one
which is some kind of finder if you have
a computer controlling everything you
can just plate solve which means it
takes a picture of the sky and then it
knows where it's pointed and it can
adjust but when you don't have a
computer connected you can't rely just
on go to using them out because a lot of
times it's not super accurate until you
train them out so what you need is a
some kind of finding device basically
just a wider field of view that's going
to point at the sky and sort of tell you
where you are pointed so you can make
adjustments I have a bunch of different
ones here just to show this first one
that I'm gonna show is a scope stuff
green laser and this has a little mount
on it so that I can just put it right
there in the shoe mount on the DSLR and
then just press that and I get a laser
okay so this would tell me where I'm
pointing it just by shiny and green
laser out into the sky and I see that
laser beam going out into the sky and I
know where I'm pointed then I like this
a lot it's very easy to use and very
accurate but the problem with using this
is right now I'm in a populated area
near the Philadelphia Airport so this is
frowned upon because you don't want to
accidentally shine the laser at an
airplane and blind the pilot or
something like that so don't use this if
you're anywhere near an airport but if
you were out somewhere really dark with
no airplanes this might be a good option
another option
I use this a lot when I'm doing visual
astronomy this is what's called an RA CI
finderscope the RACI stands for right
angle meaning you can look down into it
rather than having to be back like that
and the CI means corrected image so it
instead of reversing the image in there
its corrected so I really like this very
easy to use you can just put this on
either of these little brackets right
here and tighten it up and then you have
a nice finder scope I don't usually use
this one for astrophotography just
because I don't know why exactly but
it's just it's a smaller field of view
and I just find it takes a little bit
longer to find things with this for
visual astronomy I don't really care I'm
actually with visual astronomy usually
looking at pretty bright objects like
the planets and things like that so this
works perfectly fine but for dimmer
stuff I like seeing a broader field and
this one sort of limits your field it's
probably not much wider field of view
than just looking through the camera so
I use this more for visual like when I'm
using a Dobsonian will it show next year
tell rad this is probably my favorite of
all the finderscope designs what this
does is it has a leveling base so you
can really are leveling thing right
there actually so you can really make
sure that it's aligned with your
telescope and this also I can just slide
in right here
that and you can see it's sort of
elevated and what you do is you just
look with both eyes and you just look
right through like that and turn it on
right here and it puts a little red
target on to the sky and that's all it
is it just puts a little red target on
to the sky right in there and I find
this really easy to use and really
accurate because I can just see that red
target and get the object perfectly or
the star perfectly centered only
downside with this is that sometimes
this piece right here fogs are Frost's
up and then it becomes unusable all
right last one you know a lot of finder
options this is the one that I'm
planning to use when I'm bringing this
rig traveling because it's the smallest
and lightest of all these options this
is a red dot finder this is just a
no-name brand red dot finder I got on
Amazon it's also adjustable so you can
make sure that you're pointed at the
same thing with this and the telescope
before you start finding stuff with it
and then it turns on right here maybe
well maybe that was an adjustment whoops
turns on here there we go and so what it
does is it puts a little red dot in the
middle of this and then you just look
through that again you can just use both
eyes open at the sky and just like this
one it just puts a little red target
where you're pointed the only difference
between these two really is that this is
just one little harsh red dot and that
is a more adjustable big target thing
and so I like that one a little bit
better in terms of just looking at it
this one the field of view is a little
bit smaller you know this little target
thing you're smaller than that and
sometimes I have to sort of squint to
see where exactly I'm pointed with this
one but for travel you probably could
can't beat this it's also incredibly
lightweight so this adds basically
nothing to the weight of this whole
thing right that's enough on finders but
probably essential with something like
this where you don't have computer
control to use some kind of finder
okay now I'm gonna go through some tips
and things to do with this equipment
before you take it out first thing is if
all this equipment is new to you
I don't remem
light or something it's still really
hard to really get to know your
equipment for the first time in a dark
setting so I would recommend working
with it you know inside or on a sunny
day and just really playing around with
it and making sure you understand how
everything works another thing you can
do on a sunny day is find the about the
right Infinity focus for your telescope
with your DSLR you can just point it at
a like a far-off thing like a radio
tower or a cell phone tower and then
just wrack the focus in and out until
you have sharp focus and then you can
either just leave it like that if that's
an option or you can just note how far
out it is this one's really nice because
it has a scale so I can just see okay 22
millimeters out is about the right focus
that's a really nice thing to do before
you bring it out under the stars because
one thing that often confuses beginners
is if you're too far out of focus like
if I was like that and I looked into my
DSLR I probably just wouldn't see
anything even though I'm pointed at the
night sky I have my lens cap off it just
looks completely black and a lot of
times then a beginner would just assumes
something's really wrong what's going on
here this isn't working and you know but
all they would have to do really is just
rack the focus in and out and eventually
you'll see the stars come in they'll be
really blurry at first and then they'll
get more pinpoint the reason though that
when you're really far out of focus it
that you don't see anything is because
that light from that stars just scatters
way too much so you just don't see
anything in here when you get it closer
and closer that light cone comes
together and then
eventually you get those pinpoint stars
of just what you want okay and then so
if you have it at about the correct
focus when you start then you can just
move to this fine reduction knob and
just fine-tune it either by eye you can
just try to get the star as small as
possible or you can use a badenov mask
which i've covered in another video but
it's basically just a pattern that you
put in front of the scope here and then
you make a reproducible pattern on your
live view and you can adjust it until
this spike is centered between two other
spikes get one if you've never tried
that they're really fun to use other
thing you would want to do before going
out other than getting to know your
equipment is make sure you have all
fresh batteries fresh SD cards and
backups so I always bring backups of
everything I can you know definitely
batteries and memory cards but anything
else like even finder scopes I'll bring
backups because things will go wrong you
know there's tons of problems at night
due and Frost and all these things and
batteries will drain very quickly
because it's cold out
so bring backups of everything what else
we want to make sure that we've set a
number of camera settings on a DSLR
before we go out because a lot of times
if you don't do it before you go out at
night you get excited and you've missed
some crucial camera setting like you
have it set on JPEG or something like
that and then the night is sort of
ruined so I always make sure that some
camera settings you know you can't pick
them all right away but some of the
basic ones are set inside before I leave
the house so I'm going to show you a few
of those now
okay we're now gonna look at camera
settings this is again a Canon t6 I
however I think these camera settings
will be will make sense no matter what
model of camera you have but some of
them you know in terms of the location
and things and menus might be a little
Canon specific but hopefully you'll be
able to find all this stuff in Nikon or
whatever camera you have so I've just
turned on the camera it gives me this
screen right here which shows me a few
good pieces of information down here
this number in the that corner is the
number of exposures that I could do but
keep in mind this might be set on JPEG
so this number might be lying right now
right there's my battery indicator so I
would always want to make sure I have a
charged battery before going out because
I have a telescope attached it
automatically switches to manual focus
which is good and it also doesn't give
me an option to change the F number
there the aperture setting because it
knows that it can't if some on Canon
lenses and lenses meant for this system
you could change that number with the
aperture blades
you know stopping down the lens but with
the telescope it's fixed is enough six
scope in it is always f6 unless you get
a reducer okay anyways that's all that
the first thing I noticed here is in the
upper left we're in aperture priority
mode for astrophotography we either want
to be in manual exposure mode or if your
camera has it bulb mode perhaps if you
want longer than thirty second exposures
next thing I'm going to do is we're at
one sixtieth of a second in terms of the
shutter speed on a manual mode I'm gonna
change that to six or maybe ten seconds
something like that because even if
we're planning to take 30 second
exposures and
and when I'm just doing my testing you
know testing focus and things like that
under a dark sky I usually want
something around five to ten second
exposure some to ten seconds next thing
I'm going to do here is I can see we're
on auto white balance
I don't want auto white balance I'm
gonna hit Q here move up to that one and
change it to daylight white balance if
you are not using any filters and a
stock DSLR you want daylight white
balance if you are using something like
a light pollution filter you would
instead want to set a custom white
balance where with the filter on you go
out and take a picture of something
white like a white card with that filter
in there to make a custom white balance
but since I'm not using any filters I'm
gonna use daylight white balance if you
just leave it on auto white balance
that's not going to be good because
it'll change the color temperature of
the scene automatically but it doesn't
know what it's doing because it's night
so daylight's better what else here so I
can see some other things I know what
some of these symbols mean but most of
these other things we're going to change
in the menu one more thing on here
actually we can change which is the ISO
so right now it's set to auto I'm just
gonna go ahead and put that on 1600 1600
might be too aggressive once we get out
there we might you know bring it down to
800 or 400 but I usually start at 1600
or even higher because when you're just
doing those test exposures to see what
you have make sure things are in focus
and not streaking it's nice to have a
high ISO like that okay now I'm gonna go
ahead and hit menu here and this first
menu screen on a Canon all the way over
on the left the first thing in there is
image quality you could also think of
that as a file format all of this top
row here and these two on the bottom row
are JPEG options so right now it's set
on
large JPEG for astrophotography you do
not want JPEG you want raw you might
think well why not get raw plus JPEG
there's really no reason to it's just
going to fill up your memory card faster
and you're just gonna throw out those
JPEGs so just do raw that will just
capture the proprietary RAW files for
whatever system you're using Nikon or
Canon or Sony all of different raw file
endings but the astrophotography
software that will show will handle all
of those I would disable any beeping or
anything like that it just gets annoying
under image review you want to set this
to off what is image review let me show
you a I'll go ahead and take a picture
here oh it's a ten-second picture so
this is gonna be just pure white
shouldn't be said that okay anyways
there we go
that little two-second review of your
picture is good when you're doing like
you know regular photography but for
astrophotography you really don't want
that because for one it will ruin your
dark adaptation of with your eyes really
sort of blind you at night and two it
will drain the battery faster three this
is a minor issue but it might raise the
heat of electronics and the sensor up a
little bit and with without cooling its
you really want to try to keep the
camera as as cool as possible so any
anything that can raise the heat inside
the camera is bad so we're gonna turn
that off image review off you can always
just hit the playback button when you're
doing some testing to see the picture so
you don't need that alright let's see if
there's anything in here this doesn't
really matter because it applies to the
JPEG transformation I believe but I just
like to set the picture
style dat neutral again I don't think
that matters colorspace I would suggest
putting this in Adobe RGB I'm not sure
again if that matters but that's what
I've always done long exposure noise
reduction you might think that sounds
good
don't want that I always turn that off
you know some astrophotographers who try
to save time might disagree with me but
I think what that will do if I turn it
on is basically take a dark within the
camera and apply that to the picture
that I just took but all of the
workflows that I'm going to be showing
we take dark separately and apply the
darks ourselves so I always just
recommend you to leave that off high ISO
speed noise reduction off again I don't
know if that applies to the raw file I
think what it's saying down here is that
it doesn't but let's just turn it off
anyways basically any like thing you can
turn off in here you probably want
disabled it off nothing in there really
matters blah blah
if whoops
if you you know your memory card was
pretty full you might want to take the
pictures off of it and then format the
cards here starting out with a nice full
card auto-rotate this again I would
recommend turning off I've had some
issues with that in processing so I
don't want it to rotate my picture so
I'm going to turn that off auto power
off you might want to turn that disable
that as well I'm not sure about that I'm
actually just gonna leave it on but put
it up to eight minutes because I
actually might want to save battery if
I'm not doing anything and I just
accidentally left the camera on okay I
think we're done so gone through all the
settings that matter in the menu the
main thing if you forget all that is
just make sure you're set to record RAW
files if I get out of the menu here you
can see because we switched it to raw
and I'm using a fairly small memory card
the number of pictures we can take has
gone down and substantially but that's
plenty because I'm only planning to make
me do a hundred pictures of Orion
tonight and even with darks and bias and
everything we should be fine but we
might almost fill the memory card once
we get all those calibration frames
while I have the camera set up like this
one more thing I'd like to point out
with the t6i here it's really nice is it
has this swivel screen which I can
actually point up so you might think
yeah who cares but this is a huge neck
saver because when the when you don't
have a screen that can point up like
that and it's just fixed to the back of
the camera most of the time this is
going to be pointed down at very low to
the ground so you basically have to lay
down on the ground to see it and this
where you can swivel out the screen and
point it
and see it like that and then this is a
touchscreen is huge in terms of ease of
use with the DSLR and no computer if you
control it with the computer doesn't
really matter backyard iOS is a nice
program for that but if you're if you
don't want no wires you just want the
DSLR there I would for getting a new one
get one that has a screen like that that
comes out and you can swivel so other
than making sure I have all the
equipment I'm going to use that I have
fresh batteries that I understand how to
use it that the camera has the correct
settings what else do I do before I
leave the house planning of course I
have a whole video on this so I'll put
that as a link here but I just want to
show since I'm showing every step of
this m42 process what I would do to plan
for m42 with some basic equipment it's
not going to be super involved but let's
jump on the computer and I'll show you
what we can do with Geo so browser to
make a plan for tonight I'm going to
start with this free donation supported
web site called DSL browser if you are
interested in this how to use this
website I have another video which I'll
link through an annotation right here so
you can find it that's all about
planning for DSO imaging sessions and I
talked a lot about this website and how
to set up your profile and all of that
so if you're interested go ahead and
check out that video today I'm gonna go
right here - Oh Ryan Nebula because
that's what we're gonna be shooting m42
and just point out a few things on this
site that helped with planning one is
that right here we can see some amateur
images of it which is nice and down
there it gives us some information about
how they shot it so like I can see this
person used ISO 1600 so that might give
me a clue that that might be a good ISO
to use or something
that Alright after looking at these
amateur images the next thing I look at
appear at the top over on the right is
the hourly altitude of the object and
this is for my location that I set in
here so it knows where I'm going to be
shooting tonight and that's how it can
know the altitude of the object at these
different times and so if I just move my
mouse over this curve I can see at
around 10:30 it's a 25 degrees at 11:30
it's a 35 degrees at 12:30 past midnight
it's a 40-something so one thing that
you need a little experience to be aware
of is when objects will get over the
treeline for whatever site you're gonna
be shooting from and that's not
something you probably know right away
if you're a beginner but generally if
you're thinking tall trees 3540 degrees
is about where you're gonna be looking
at but generally tall trees I'd say
above 35 degrees most object or an
object will get you know past the
treeline that's sort of what I
generalize that is about 3540 degrees
you're gonna get past any trees and so
for this object that's around midnight
tonight now you might think so should I
just not go out to like 11:30 I wouldn't
advise that it's really much easier to
set up as the Sun is setting if you can
if it's like a Saturday and you have all
day
because especially when you're new to
this it's much easier to set things up
in daylight rather than in the dark but
then I have all of this time before I
can actually shoot Orion so what could I
do during that time well I could shoot a
different object I know for instance
that the Pleiades m/45
is available right now so I could shoot
that until Orion comes up the other
thing I could do is I could shoot my
calibration frames first because some of
those take longer than others bias and
flat frames won't take very long just a
few minutes to shoot but darks can take
a while so let's say you're gonna shoot
a Ryan for two hours tonight you may
want an hour to of dark frames to
calibrate the what we call the light
frames the actual object you're shooting
so I'll talk more about calibration
frames later but just to say that this
time up till midnight won't be wasted we
can shoot another object or we could
shoot calibration frames but it's
helpful to think about these things
before you leave the house let me scroll
down here over here is a nice little
data sheet about the object so I can see
it's magnitude 4 that's pretty bright
even in a light polluted area you're
gonna be able to see that through any
kind of telescope it's one-and-a-half by
one degree that's the size of it and if
I keep scrolling down here this is a
really useful tool built in to DSO
browser where I can pick from my
different objectives here my different
telescopes and tonight I'm going to be
using the Astrotech 60 millimeter
refractor and I can pick from my
different cameras here I have the Z wo
in there but tonight I'm gonna use a
Canon and then it gives me this nice
reticule right here on top of DSS
imagery showing me the object right here
and I can rotate that reticule with this
orientation slider right here so if I
wanted to do a more vertical shot I can
see how it looks like that or if I
wanted to do really horizontal something
like that I think I'm gonna do something
like this where it's like it a little
bit of an angle
this right here this bright part is
Orion and then this little part right
above it is the running man nebula
alright I think that looks pretty good
and so one thing that I will sometimes
do now is all take a screenshot of this
and I'll open up that screenshot in
something like Photoshop but it could be
whatever image editing program you're
comfortable with and I'll invert it then
it's just a little bit easier to see the
star pattern I'll maybe make it
grayscale because I don't really need
the colors there just to see that star
pattern really clearly and sometimes
I'll also play around with curves a
little bit just to add a little bit more
contrast so that those stars and the
dust is really clear so I can really see
the framing now and how that's going to
look on my sensor and then I might print
this out or send it to my phone so I can
look at it later when I'm doing the
framing so that's about it then we're
gonna I'm going to do in the computer
for this object
like I said we're keeping it pretty
basic today so I'm not doing a huge
amount of planning we're doing what's
called a one shot color camera OSC so I
don't have to think about filters or
anything like that
and in terms of a plan I'm just going to
shoot this as long as I can I think
there's gonna be some clouds coming in
tonight so I might only get I don't know
an hour on it or something like that but
we'll just shoot it as long as we can
and
in terms of the amount of time to put
into each sub exposure I'm somewhat
limited by my mount tonight and also the
fact that I'm not going to be guiding so
probably can't do really long exposures
anyways so I'm gonna try 30 seconds and
then just set the ISO based on what the
histogram bump looks like so I'll
explain all that later when we're
actually doing it but that's my plan I
can print this out or send it to myself
now so I have an idea of the framing and
we're ready to go yeah we have a nice
night here in Delaware the moon is
setting over here to the southwest and
Orion is rising over there to the
southeast and we're about ready to get
rolling here I've already set up the IAP
tron tripod as you can see and you
really when you're doing extra
photography you don't want to raise this
any higher than is necessary the legs
would extend and make this quite a bit
higher which makes it a little bit more
comfortable to use but that's really
just for visual use so that you're at a
comfortable plate height for the
eyepiece for astrophotography you want
to keep center of gravity as low as
possible so this is how I have it here
I'm just gonna put in this tray okay and
I'll go ahead and make sure this is
level just by using a little level on my
phone here yep that's pretty good
I also can check that this pin right
here is roughly pointed north because my
leveler
it's part of PS align Pro which is a
true dialer app also has a compass built
into the leveler so I can see that's
north which is good
alright next step is I'm going to take
out the mount head here and with the IAP
drawn when to fit it back into the case
you have to take out this bolt and then
put it in each time and what this bolt
does is it's the latitude or the sorry
the altitude adjustment all right got
that bolt in there I can just put this
on to the tripod here
and right below the mount head is the
screw here to attach it and secure it to
the tripod okay
that's now securely on there and I'm
going to release the counterweight shaft
ring like that and take off this piece
and on the back here take off the cap
and there's a polar alignment scope
built into this and I often like to look
through it before I turn the mount on
because once you turn the mount on you
usually get a pretty glaring red light
but I like to sort of make sure I can
see Polaris through the polar alignment
scope before I turn on that red light
because if it's not even in the field of
view then it's hard to find Polaris with
that red light on and to do this I'm
gonna have to turn on the light lighting
on me for a second here so bear with me
it's going to go dark
okay now the polar alignment pull master
is on there I'm going to go ahead and
install a counterweight on the Conor
white shaft just like so and I'm not
sure where on the shaft this should go
yet because you have to do that with the
telescope up here so you can balance it
that's good enough for now
and I'm not going to turn them out on
yet I'm just going to get ready here by
putting attaching my hand controller
here and I've put some little figure
what they call these waterproof velcro
for that just to stick on the front like
that okay ready for the scope
hey now let's go ahead and balance
alright so see how it's it's falling
this way towards the counterweight I
want to get it so that it's just
slightly falling to the counterweight
side
but basically balanced this is called
getting a little bit east heavy not
having quite perfect balance but pretty
close okay that's good
okay now I'm going to do the fine polar
alignment and again I'll have to turn
off the light to do this but basically
the idea here is you just tell the
software
what do your axis of rotation is and
then it looks at the patterns of the
stars around Polaris and you can get a
very fine polar alignment using this
electronic scope and your computer but
again this is optional
another way to get a fine polar
alignment is through what's called drift
align which you can look up it's
basically just watching the Stars drift
on your DSLR and fixing the plural in it
that way all right so I'm going to turn
off the white
okay now I've done a great puller
alignment with the pole master I'm gonna
go ahead and turn the mount on this
mount runs off eight double-a batteries
or it can also run off 12 volt or
battery a bigger battery it has a socket
here go ahead and use this to put in
information here again I use PS align
Pro two for my GPS coordinates so I'm
setting what's called the time and sight
in here and then I click on set zero
position which just tells it it's this
counter way down pointing it Polaris
position and now we're ready to go so
I'm gonna go ahead and just go to they
call it select and slew in the menu here
I'm gonna go to m42 and the mount starts
slowing it's going in the right
direction
besides a good sign
once it gets there I'm gonna use this
tell rad which is just a type of
finderscope
to Center and pretty to a little bit
better before turning on the camera and
doing some more framing in there all
right unfortunately I'm gonna have to
turn off the light once more
okay I've centered the target using the
towel rod here and then I turned on my
DSLR and it was right there on the LCD
and I recognize these as the stars
around their Ryan Nebula but for a
beginner you might not but then all you
have to do is just take like a 10 second
exposure for instance
and take a look at it and there you see
Orion right there in the middle this
framing looks pretty good you just take
a look here yeah I like that sort of
going sideways here with the running man
up there just see if I can see it
without all this stuff there we go maybe
I'll just push it down just a tad so
yeah I think that's good okay and I'm
just gonna go ahead and pump this up to
the 30 second exposure which is my what
I was hoping for just make sure I'm not
trailing the stars or anything and I'll
also take a look at the histogram just
to show you how you can evaluate if you
have a good exposure level it looks
super bright but that's usually okay
let's zoom in on the stars here yeah
what I do
those stars look reasonably around but
it's a little bit hard to tell because
we are not focused that's something I
forgot to do so let's go ahead and focus
use a live view
get a zoom in
I'm going to find my focus here and you
can see when I go that way star is
getting bigger we're seeing sort of the
pattern there when I go this way
eventually it gets bigger again but
really out of focus there so what I'm
going for is trying to get that star as
small as possible
and the other thing I can try here is I
have a bad enough mask this star might
not be bright enough but let's go ahead
and try it okay it's just bright enough
that I can probably do this might be
hard to see on your screen though there
right there is focus I can see the
pattern of the badenov mask and you just
want to get that central spike in the
middle see that's out that's out that
way that looks good just to test that
I'm gonna go ahead and take a 6 second
exposure with the bad nut mask on
yep that looks good okay zoom in further
so you can see what I'm seeing here see
that so that's good focus with the
badenov mask that central spike is right
in between the other two and I'll go
ahead and take it off now and do what I
was doing before which is taking a 30
second exposure see if our stars are
trailing and if this is a good exposure
level
all right zoom in on this guy doing that
sorry
those stars do not look like they're
trailing at all but I have a little bit
of a streak that's just because I was
hitting the trigger but stars look good
I'll check the level now which I just
get by hitting info here a couple times
to zoom out first
there's our histogram it's actually a
little bit too far over we only want it
about a quarter to a third of the way
over so I'm going to turn down my ISO
and try this again turn it down to 800
check it again there we go so a quarter
to a third of the way over it looks good
let's check our stars again the stars
look perfect so we're ready to go so
last step here so I'm going to take my
intervalometer here
and just make sure it's set right 31
seconds that gives a one-second gap
between them I'm gonna take let's say
try for 50 shots I don't know if won't
get that before it hits the trees but
we'll try it
go ahead and get out a live view here
close this up and start alright now
we're gonna do the calibration frames
I'm gonna start by taking my flats here
you can see I have a LED panel that I
use and I also have this little cap
diffuser but you can just use like a
white t-shirt that works fine and you
don't need the white LED panel either
you could this is just what's called a
tracing panel I got an Amazon but you
could instead use like a iPad or a
laptop screen turn to white I'm gonna
put that on top here and that's about it
in terms of setup just you just want
something white and diffuse and filling
the entire field of the scope and so you
can either use a screen like this on top
or you could shoot sky flats just
pointing at the sky with some kind of
diffusion or even just like a white wall
that's evenly lit so let's look at the
back of the camera here so we can see
the settings for flats basically I just
use the same ISO that I gonna use for my
lights and then I just sort of
experiment with different exposure
length settings here or it also called
shutter speed on a DSLR until my flat is
about half the way over doesn't have to
really be quite half because I won't get
into it but this is a JPEG histogram
it's not the raw histogram so really if
you under shoot a little bit that that's
just fine
and some people do this with aperture
priority that's another option for
taking flats and I'm gonna take about 50
of them okay for the next group of
calibration frames we want the front
lens cap on so I'm just going to put
that
here because these are both done in
darkness and I really all you have to do
is just put that lens cap on you also
want to make sure that you're at around
the same temperature as where what
you're shooting your lights at so we've
been out here a while I've let the the
scope and the camera cool down it's
mostly that the sensor that you're
worried about being at the same
temperature so let's start with bias
frames those are really easy and quick
to do we'll look at the camera here and
all we have to do on the camera is turn
the shutter speed all the way up by that
I mean the fastest that it can go so in
this DSLR that's one four thousandths of
a second it might be different on your
DSLR it might be one eight thousandths
of a second but the point here is you
just want a very very short exposure and
this is going to reveal what's called
the fixed pattern noise on the camera
sensor I'm gonna use my intervalometer
here to take a bunch of them with bias
frames I usually take at least a hundred
if not more to really get a nice idea of
that noise that's fixed to the sensor
and finding those banding patterns and
things like that you really want to a
lot to average together so I'm going to
type in a hundred here and let it go
okay and for our last calibration frames
the only thing we have to change here is
the shutter speed these are darks and
we're just gonna change the shutter
speed to what the same shutter speed
that we're gonna use for our lights in
which in my case I've already decided on
30 seconds so I'm going to change it to
30 seconds here and the number of darks
are gonna take right it's always more
the better but usually you don't have to
take you no more than 30 or 50 or
something like that with 30 second darks
I might as well take a bunch but if you
were doing like five minutes of
exposures that could take a long time so
usually around twenty or thirty is is
fine and the only other thing with darks
is you just want to try to match that
temperature as well as you can so if you
think that it's gonna keep dropping in
temperature you would want to do them
closer to when you shoot the lights so
that that temperature stays stable all
right I'm gonna let this go and take
about thirty okay first thing you're
gonna want to do after you've had a
successful night of imaging is get all
of your files off of your DSLR and on to
your computer and I like to put
everything in one folder so you can see
I've started a folder here for this
project and then I organized things like
this I put my bias my darks my flats my
lights all into their own folders and
then I have a new folder for processing
files and so I've already taken the
files off of the camera and put them
into the appropriate folders here but I
think it's interesting to look at what
these files look like on their own
before we do anything with them so let's
take a look if you have any kind of RAW
processing software on your computer you
should be able to just double click one
of these to open it up like Adobe
products or a raw table or dark table or
there's a bunch of GIMP there's a
two different programs you can use to
look at these I'm just going to use
whatever comes up here probably
Photoshop look at these different files
okay so this is a Photoshop Camera Raw
Dobby Camera Raw it recognizes the DSLR
that this was shot with which was again
a t6i it recognizes that this it was
shot at 1/4 thousandths of a second so
that's a bias frame iso 800 and all i
want to show you here is what this looks
like in this state it doesn't look like
much at all but if I really just stretch
the exposure here you can see that there
is a lot of noise here and also these
sort of alternating dark and bright
lines that is the fixed pattern noise on
the sensor and we want to subtract that
out of our flats especially it would
also be included in the dark frames so
the point is really to calibrate your
flats properly because your darks are
going to be exposed for your lights
while these bias frames can be used to
take this pattern noise out of my flats
so I'm not adding noise when I divide
the flats out okay so that's what those
look like let's go ahead and open up a
dark it's gonna look pretty similar I'll
stretch it here with this little
exposure agai and like I said it looks
very similar if we really stretch it out
these bright pixels are hot pixels you
can see that it has that same fixed
pattern noise the horizontal banding of
the bias frame and this is to handle
dark current noise in our lights so
since I was using an uncooled camera
there's going to be some heat buildup on
the sensor and this is to calibrate that
out
and let's look at a light frame so sorry
flat so this is the last calibration
frame and it's really important a lot of
people forget to shoot them
let me just mess around with this a
little bit to sort of show you what this
does okay so might be hard to see
let me just accentuate it a little bit
further
I don't know if that helps what this
does is it's trying to model I've been
getting in the system so I've been
getting is where the corners are darker
than the middle because they're not
receiving as much light and so this
looks like a pretty flat frame already I
was trying to accentuate there we go
that you can see once we stack them
it'll look a little bit more like this
probably where the middle part is
getting more light in the corners which
are darker and so that's what this is
trying to model it can also if there's
any dust or what we call dust and donuts
in your system like dust falling
anywhere in the optical train you can
also model those and divide those out so
flats are very important to take this is
an example of what one looks like and
not much else to say about that so I
mean I have it and cancel open up a
light and lights are your pictures of
the actual object and I think we did
about 70 of them here at 30 seconds each
and so this is what a single light frame
looks like this is with an auto stretch
what's called a gamma curve applied but
so without anything done to it this is
what a light frame looks like if I play
around with these sliders a little bit
let me bring up the exposure bring down
the black level bring down the contrast
bring down the highlights a little bit
bring up the clarity change the
temperature just a little bit here
this is about how much detail we get
from a single exposure and it's very
hard to see but you can see in a single
exposure here we do get some of the
outer nebulosity but that will show up a
lot more when we stack you can see in a
single exposure we don't see much of the
running man here but again after we
stack 70 of these a lot of that will
become clear because right now it's lost
in the noise and it's also lost in the
light pollution gradient here but you
can see in a single exposure we do get
some nice detail and the other thing we
would do when looking through these
single exposures is reviewing that each
one is doesn't have any mistakes in it
like that the stars are reasonably round
and in focus in this light after I've
messed with a little bit here you can
see the vignette in on the corners so
again that's what the flats are supposed
to take out so we can use more of the
frame all right that's it
I'm gonna cancel out of that so that's
our four different frames once we have
these all sorted like this on our
computer we can move on to the next step
in processing which is calibrating our
lights stacking our lights after
registering them to each other using the
Stars to register and we're gonna look
at some different processing methods to
do that we can try deep sky stacker and
Photoshop or GIMP and then we can also
look at it how to do it in pix insight
okay here we go
with deep-sky stacker this program is
Windows only but it is free and what it
does is it registers your light frames
it calibrates them
we have darks flats and bias files and
it stacks all of that together and can
do things like Sigma clipping to get rid
of things that are abnormal like hot
pixels and and just airplane streaks and
all that kind of stuff
and it's a very easy to use program once
you get the hang of it
it does this one thing very well which
is stacking and doesn't do much else so
let's look at it we're just gonna use
the basic features of it here we start
over here in the upper left hand corner
by clicking open picture files I'm gonna
click on that and find the light frames
for the object that I'm working with so
if you've already organized like I have
here it's pretty easy you just go into
the m42 folder click on the lights
folder and there's all the files if on
your computer you are not seeing your
files for some reason just make sure
that down here it's not set to something
weird like JPEG only or picture files
it's set to just all files and then you
should see all of your RAW files I'm
just gonna click on one and then press
ctrl-a to select them all and then click
open okay what I can do here in deep sky
stacker is click on one I'm just gonna
click on the first one and it gives me a
nice little preview here of the file
we're not seeing much other than the
really bright stars here if we zoom in
we can see that there are dimmer stars
as well but if I wanted to brighten this
picture up a bit this is just for
preview purposes I can go up here to the
upper right and drag this middle slider
in a bit to the left and it brightens up
the picture some and I can
some of the dimmer stars now which is
helpful for evaluating focus and also
how much elongation of the stars there
are and in every frame deep-sky stacker
can do some stuff with evaluating the
Stars for you but if you want this more
manual control it's here for you you can
zoom in you can look at the pictures you
can go through them one by one takes a
second for it to load each picture you
can zoom in on this one and I can decide
is this a frame that I want to keep or
do I want to get rid of it
and I'm not gonna show that whole
process but I'll just show you an
example of a frame that you would not
want to include let me go all the way
down to the bottom here and I remember
at the end of the night my last frame I
must have hit the tripod because there's
like a little jitter in it let me zoom
in on this okay and you see that that's
on all the stars that little jitter on
all the stars that's from knocking
something or stepping too hard or
whatever and it can also happen from
wind but basically we wouldn't want to
include that frame so how do we not
include this frame what we want to do is
we first want to check all so I'm going
to go over here and click check all and
then I'm going to just uncheck that last
one that one I don't want to include
just by clicking its little checkbox
here to uncheck it okay so we have 71 of
72 light frames checked now we're gonna
go ahead and add our dark frames click
on dark files over here I'm gonna hit
control a to select all my darks those
if we look at one of those I'm just
going to click on one here it doesn't
look like much if we really stretch it
still doesn't look like much
but that's what darks are they're
basically just correcting for hot pixels
and thermal noise things like that let's
go ahead and add our flat files control
a to select all of these click open
brings in our flats let me stretch this
a little bit so you can see what it
looks like too much there we go
so you can see that it gets a little bit
darker towards the corners here that's
representing the vignetting I don't know
how clearly you can see that but that's
our flat frames and last our bias frames
let's add these control a to select them
and we have 100 bias frames in here
let's see if we can see anything in the
bias it's sort of hard to see anything
but basically that represents the fixed
pattern noise on the sensor and it can
get rid of horizontal and vertical
banding problems that it is common with
DSLRs okay so we have all of this added
now and remember with that last light
frame I unchecked it looks good if we
want we can look at the raw settings
which are down here under options raw
settings and these are the same as the
last time I set them up I just use this
default Bayer matrix interpolation I've
always used camera white balance because
I'm always careful to set that if you
didn't just uncheck that to not use it
at all I always set the black point to
zero
which helps with calibration I believe
and if you change any of these just
remember to click apply before you click
ok next thing I'm going to do is over
here on the left hand side under
register
cheering and stacking and click on
register checked pictures it brings up
your register settings these will be
whatever you last set them at so if you
want it to automatically detect and
remove hot pixels make sure just to
check that I'm going to do that if
you've already registered the pictures
you can use this option right above
there but I haven't registered these
together yet I mean putting them all on
the same place so the Stars match up so
I'm gonna leave that unchecked I want to
check stack after registering cuz I do
want that to happen and right here it
says select the best percentage pictures
and stack them you can change this to
whatever you want basically it just
assigns a score to each picture based on
how round the stars are and if you only
wanted to include like the best 50% or
80% you can set that right here if you
want to include everything just put in a
hundred percent I'm gonna put in 97
percent because maybe there's one that I
didn't catch that it could throw out
next thing I do is I go over here to the
Advanced tab and by default it sets this
star detection threshold to 10 percent
you may not need to change this though
to get a good number of stars if you're
below let's say 50 stars you probably
want to change the detection if you're
above a thousand stars you might also
want to change that detection because
they might be picking up hot pixels and
things like that so I'm gonna go ahead
and click on compute the number of
detected stars it looks at the first
light frame and sees how many stars it
can find looks like I have plenty here
it found almost 300 so that's fine I
could just leave this alone at 10
percent but if I wanted to speed this up
a little bit I might take this down to
20 percent I'll compute again
and now it's down to 177 stars so it's
just fewer stars to match against
usually works a little bit faster and
better so I'm going to leave it at that
I'm going to go ahead and click on this
reduce the noise by using a median
filter and then I'm gonna click on
recommended settings and basically you
can just step through this and any time
where it's highlighted in blue here you
can read what it says if you were using
a modded DSLR well I'm not so I'm going
to ignore that if you are processing
narrowband images I'm not so I'm going
to ignore that one and then you just go
through each one and if it's something
that you haven't done you can just click
on that and it will put that into your
recommended settings I'm using Sigma
clipping I'm using bilinear d bearing
and blah blah blah so you can go through
there make sure you have all the
recommended settings click OK if you
want to go into stacking parameters and
look at these this has much more detail
I'm not going to go into all this right
now because this isn't a video about
deep sky stacker it's sort of an
overview of all the processing so this
would take too long but there are other
videos online so if you're interested
you can learn about all these different
settings in here this is good enough
though we're gonna go ahead and click OK
and it gives us a nice summary here of
everything we're gonna be stacking 72
light frames with offset or bias dark
and flats specifically a hundred bias 25
darks and 29 flats the total exposure is
38 minutes 24 seconds all looks good I'm
gonna go ahead and click OK to start the
process and off it goes it starts by
stacking together all of your bias or
offset frames into a master bias it then
does the same thing for darks and flats
it then calibrates all your individual
light frames with those master
calibration frames and then registers
and stacks your light frames into your
final single integrated image which you
can then preview here in deep sky
stacker but usually you just save it off
and we move on to Photoshop or GIMP so
I'm gonna speed up this part of the
video because it's gonna take at least
10 minutes probably more like 15 or 20
and then we'll I'll show you saving out
of deep sky stacker when this is all
done
okay so what it's doing right now is
it's saving the autosave dot TIFF file
to my lights folder this is important
this is a 32-bit TIFF file that you can
consider your master stack Photoshop can
actually read a 32-bit TIFF file so you
could bring it right into the autosave
dot TIFF right into Photoshop not all
features in Photoshop are 32-bit so you
might have to eventually convert it to a
16-bit file if you're going to be
working with GIMP it probably can't even
open that 32-bit file so we're gonna
have to first save the picture to file
which is over here on the left hand side
under processing and save it as an
uncompressed 16-bit TIFF one thing
that's a little bit confusing here about
deepskystacker is it's making the final
picture right here on screen and there's
a bunch of settings we could change
right here and deep-sky stacker but it's
not really meant as a processing program
it's just a stacking program so really
there's not much point in doing much
here because we're not going to save
these changes anyways so I'm just going
to leave all that alone and go over here
to where it says save picture to file
and I'll just save it here to my desktop
to my m42 folder and I'll call it stack
dot TIFF and I mean to say compression
none and I want to just leave this
option that says embed adjustments in
the saved image but do not apply them
checked so basically just exactly how it
was and click Save okay now that I have
a stacked image out of deep sky stacker
I have moved on to Photoshop here
everything I'm gonna show today it
really shouldn't matter which version of
Photoshop you have I'm just using the
latest here but I've used the previous
version cs6 cs5 cs4 they all work pretty
much the same and we're gonna start by
opening up our stacked TIFF out of deep
sky stacker so we're gonna go up here to
the file menu and choose open and find
it here on the computer and open it up
and it looks something like that
it looks like not very impressive right
like we didn't capture much it looks
worse than maybe even just the
individual files at this point but this
is actually exactly what we want what we
took out of deep sky stacker is the
linear master so basically linear it
means the same thing is unstretched
because we want to do the stretching
here in Photoshop the other thing I'll
point out is that I saved this as a
16-bit TIFF and we can double check that
right here by going to image mode and
see that this is an RGB color and that
it's 16 bits per channel if i zoom in on
the center here it is interesting to see
that there's a lot of fine detail right
in the core of Orion there even in this
sort of quasi linear state what that
means is that once we get further into
processing this is going to get
completely blown out to keep the rest
you know to bring up the rest of the
picture but we don't want to lose that
we're gonna bring it in later so the
first thing that I always do in
Photoshop here is I duplicate this later
a couple times and in Photoshop that's
easy to do that you just right-click or
control-click if you're on a laptop and
choose duplicate layer and you can call
it something if you want I'm just going
to call mine first
stretch and as long as we do that first
and we keep this background layer as it
is then we're good because we can keep
duplicating off the background layer as
needed so with this first stretch layer
selected I'm going to go up here to
image go down to adjustments and go to
levels since we're going to be coming
back to this a few times it's good to
learn the keyboard shortcut which in
this case is command L on Mac or ctrl L
on Windows and here's our levels
adjustment this is what you're going to
use to first apply a little bit of
stretch to this and you can see that the
histogram peak here is very compressed
and what we want to do is sort of spread
it out and keep moving it off the
left-hand side here and then bringing it
back to the left-hand side and the way
we do that is we take this middle slider
and we move it over here to the left
towards where the end of the peak is
there and you can see as we do that and
zoom in again we get a lot more detail
coming up here in the Orion Nebula and a
lot more stars start to appear now we
want to do this in a bunch of successive
times we don't want to just sort of do
it all at once so I'm just actually
going to sort of do mid like that and
say okay and then I'm just going to keep
doing that press command I'll bring it
up a little bit more and just slowly
stretch it out like this now eventually
when the sky background
gets quite bright and we're sort of
losing in a detail that we're bringing
in what I like to do is take this shadow
slider this one over here on the left
and drag that one to the edge right here
and it's going to sort of look like
you're you know resetting everything you
just did
but you really are you really have
applied some stretch here just to prove
the point to you if I turn off this
first stretch with a little eyeball
indicator over here in the layers you
can see we've done a fair amount of
stretching you can see m-43 is coming in
right there
the arms of Orion are coming in okay but
we're going to keep going with this
stretch so I'm just going to press
command L one more time here I'm gonna
stretch this again press command L again
stretch it a little bit more command L
and then I'm gonna bring this shadow
slider over again
and I like to just keep looking at what
it's doing and you can see that these
the nebula is getting more and more sort
of in focus we can see more of it and we
can see this Dark Nebula coming in here
now it's pretty cool
but I'm just going to keep going with
this just a couple more times bring the
the the left-hand slider over to sort of
the edge of these histogram peaks and
bring this one in a little bit okay at
this point this is stretched enough I
can start seeing that Outernet velocity
out here on the Orion Nebula and the
fainter running man is also coming into
view and what is clear at this point is
that we have a fairly regular light
pollution gradient where it's darker up
here at the top and brighter down here
at the bottom and there are some plugins
that are really good at dealing with
this there's one called I think Astro
flat Pro and there's another one called
gradient exterminator but I'm not going
to show those partly because they both
cost about thirty to fifty dollars so
I'm not gonna make you go buy something
right away I'll show you a way to do it
just with Photoshop stools here it's not
quite as effective as those plugins but
it works okay so what we're doing here
is we want to remove this sky gradient
the light pollution is coming from the
bottom of the frame here so that's why
it's brighter at the bottom and then the
other thing you'll see here is that it's
it's fairly red that's because of when
light pollution hits the atmosphere it
creates this sort of reddish sky glow if
you're in a very dark place you might
see a more greenish sky glow but in
light polluted place without any kind of
light pollution filter your print images
will probably come back fair
redish like this in any case what we
want to do is want to subtract it out of
the picture or leaving us just with a
dark night sky and the stars and the
nebula so first thing we're to do is
we're going to go ahead and copy this
layer actually you know let's duplicate
it so you know right-click choose
duplicate and I'm gonna call this my
background removal layer okay and then
I'm gonna copy it so in newer versions
of Photoshop you just go edit copy and
that copies the layer you have selected
if you have an older version of
Photoshop you first have to select this
just do command a to make a selection
and then you'll be able to edit copy
then go ahead and do file new and it
should put in here for the width and
height whatever the dimensions of are
the thing that you just put on the
clipboard so that's good we can call
this background and go ahead and paste
it in over here in the layers panel we
don't actually need this white
background layer so I'm just going to
delete it and what we want to do with
this is completely get rid of all of the
stars and the nebula because we're just
trying to model the background so we can
come back here and remove the background
so to do that first I'm gonna to get rid
of the stars the way to do that is
through a filter so if you go up here to
the menus at the top and go to the
filter menu and go down to noise and
then choose from the noise menu dust and
scratches and you can see I've already
set mine here to something that works
but basically you're just going to take
these two sliders and move them around
so that for your picture whatever the
radius and threshold are set to it's
getting rid of all of the stars now if
you find that like here
it's not getting rid of the halo of that
brightest star that's okay because we
can take care of that the same way that
we took care of the nebula here but what
you do want to do is set this so that
for all these medium and small stars
it's just completely blurring those out
into the background this looks good
for this particular setup I'm at 58
pixel radius and three levels under
threshold I'm gonna click OK to apply
that takes a second and by the way don't
worry about if it's doing something
weird along the edges or the corners cuz
later on and processing we're gonna crop
those out anyways that's normal what
we're gonna do now though is we want to
get rid of this the remnant of the
nebula here so I'm going to grab was it
called Spot Healing Brush tool if you
don't have spot healing brush tool in
your version of Photoshop Healing Brush
tool st. does the same thing and my
version it looks sort of like a little
band-aid
and what I want to do with this is I
want to set the size to be fairly big so
I can just do this quickly so I'm going
to set mine to around 500 pixels it
doesn't have to be a particularly hard
brush I could set that to a low hardness
and I want to make sure that it's set to
the content-aware
type and then I'm just going to brush
over anywhere that there is nebula and
you might have to do it in a couple
passes here but it should go pretty
quick you'll be able to get rid of
all of that nebulosity that's in the
background there
and I usually start out sort of broad
with this and then fix smaller little
issues but usually don't really have to
change the brush size I just sort of
okay that looks good enough to me
basically this is what in pix inside we
would call creating a background model
and this is how you do it in Photoshop
so I'm gonna go ahead and save that just
press command s ctrl s on Windows and
it's saving as background PSD that's
fine then I'm going to go back to my
main picture here and with this
background removal layer selected I'm
gonna go up here to image go down to
apply image and for the source
I want background for the channel RGB
that's fine for blending I want to go
down to subtract
and then you'll probably find that you
have an offset here of zero try
different numbers there until you
basically get a fairly grayish
appearance the colors aren't going to be
perfect yet but what you want to do is
sort of get this mid gray sky so for my
camera here that was an offset of 50 you
see that if I put it at 30 that's a
little too dark 20 darker still zero is
obviously too dark I've lost a lot of
that nebulosity that I brought up
previously in the stretch so 50 looks
good to me I can see a lot of the detail
that I brought out there and the stretch
the other thing you can try here is you
can change the opacity from a hundred to
something lower so for instance 90 and
see if it's still removing the
background well enough with a lower
opacity setting 80 see now at 80 I'm
seeing a lot of that red come back so
I'm gonna set it to 90 here and the
reason I'm seeing anything as I'm
changing these numbers is cuz preview is
turned on if when you're changing these
are not seeing anything just make sure
that right there you have preview turned
on all right I'm gonna go ahead and
click OK and just doing those couple
steps stretching and removing the
background have already made the picture
a lot better we can see what the
background removal did by just turning
off the visibility of it over here in
the layers panel so that was before with
that red background and had a strong
gradient top to bottom and here's after
removing it
okay so next what I can do is continue
working basically on setting the levels
of this image we can see now that there
is a lot of interesting detail in here
there's a lot of cool dark nebulae there
and even there there's m-43 this little
piece up here that was not visible
before you get this really nice blue and
red it's a little bit dim at this point
a little bit unsaturated the running
man's barely showing up the challenge
here is we want to continue stretching
this continue bringing out the nebula
but we don't want the stars to get too
big so there's different ways we can do
this we can attack this with masks but
usually I just like to do a little bit
of stretching before I go to masks but
since this is a good sort of starting
place I'm gonna duplicate again so I'm
gonna do duplicate layer and I'm going
to call this one experiment alright and
for my experiment I'm gonna go ahead and
instead of going to image adjustments
levels I'm you know this time go to
curves and curves is just slightly
different from levels in addition to
changing the brightness you can go into
the individual color channels which is
useful and change the levels that way
and then it also just is a different
feel since it changes things instead of
sort of more uniformly it puts a curve
in there so it's you can see that with
this curve it's gonna bring these tones
right here up
other than these ones and more than
these ones when you whenever you take a
point in the middle and bring it out
like this that's going to always sort of
add contrast if you take another point
and you bring it down like that and make
this sort of S shape that's going to
really add contrast because basically
you're saying bring the background sky
level down and bring the Stars and the
nebula up so that's really going to
create a lot of contrast in the image
and it already looks a lot better but we
have to be careful with this because if
I turn the preview off and on here you
can see we're losing a lot of detail
there in the middle but the nice thing
is if I turn the preview off and on and
we look up here we're gaining detail up
there by increasing the contrast so
there's a lot of trade-offs when you're
processing astrophotography especially
objects like there Ryan Nebula where it
has a very bright core and much dimmer
outer parts and the way that I typically
deal with this is instead of trying to
create a really nicely feathered mask in
Photoshop I'm just going to go ahead and
accept that the bright the center part
is gonna get really too bright here and
then I'm going to come back in to this
background layer that I've saved told me
to show you that again and I'm going to
restore detail using my original picture
this is sometimes called an HDR approach
a high dynamic range approach one thing
that a lot of people think is that you
need you know different lengths pictures
10-second 30 second two minutes five
minutes to make an HDR approach image
you can actually do it with all the same
sub exposure lengths and it often works
out pretty well with this particular
mount I wasn't going to be able to go
too
five minute sub exposures anyways if I
could though it would make that my job a
lot easier because I would see a lot
more of this faint detail out here but
in any case I'm getting sort of off
topic what we are doing here with this
experiment is just sort of seeing how
much we captured so let me go back into
that curves and I'm just going to do a
really really dramatic curve here just
by bringing this point all the way to
the edge and then taking this shadow
point and dropping it down there okay
and this is useful just because we can
see that we did capture some of this
outer nebulosity but to bring it out
from the sky background it's going to be
pretty noisy right see all that noise
when we really take this faint part and
stretch it like this but it might be
worth it for the image let's zoom all
the way out and see what it looks like
like that looks pretty cool I think I
like how that adds something to the
image and it really to see more of the
extent of the running man I think and
how they're even sort of connected here
really adds a lot to so how do we
incorporate this let me go ahead and
just accept this curves and say ok and
I'm going to do that curves again and
bring my black point back over say okay
and the problem here is a couple things
one is that we made our stars really
ugly it made them really bloated and
bright white and the other thing is
obviously it completely blew up the core
and it brought up some detail which I'm
not sure is really worthy at because
it's just so faint a lot of people try
to preserve this dust but remember this
is only thirty minutes of total exposure
so I probably would just clip that down
into the sky because it really is never
going to add much to the picture but
maybe I do want to keep some of this
outer part of the nebula city and I like
how that looks over there too so how do
I do that well first thing is I want to
get rid of the stars in this image so
I'm just going to go ahead and do the
same thing we did before which is go to
filter noise dust and scratches but if I
just leave it on that setting you can
see that it completely blurs the the
nebulosity we can see where it is but it
doesn't look very good we don't retain
any of that sharpness in it so what I
want to do is I want to bring this
threshold level way up here to a point
where it is basically capturing the star
cores
I'm just gonna play around with these a
little bit but leaving this fine detail
in the nebula alone okay so I'm gonna go
ahead and apply that and if we have some
Star Wars that are not like that really
really bright star right there is still
in there that's fine we can clone stamp
that out later don't worry about it but
all these major large stars all that's
left is a little bit of the halo around
them that's good okay
I'm gonna go ahead and click okay and
then we're going to do that a couple
more times each time bringing down that
dust and scratches filter values a
little bit so I'm going to go back to
noise dust and scratches bring down the
radius and the threshold and you'll see
that each time we do that it cuts a
little bit more of that stellar halo
away leaving though these fine details
in the nebula
go back filter and noise dust and
scratches you can hear my computer fan
going here because this is a fairly
intensive process it's doing bring it
down this time to 25 bring the threshold
down to like 50 filter noise dust and
scratches bring it down to 19 and the
threshold down to 30 something and I'm
not picking particular values here I'm
just sort of doing this by eye and
bringing it down you know about 10 and
15 each time and you can see at this
point we've gotten rid of most of the
stars in the background but the nebula
still looks pretty detailed I'm gonna do
it one more time here there may be two
more times
mm hmm maybe not actually you see
yeah at a certain point you get
diminishing returns here I'm gonna
cancel that one all right so we still
have a few problems here though
a few areas where the star halos have
been left so to get rid of those we're
just going to use our Spot Healing Brush
that we used before but this time we
don't want it to be much bigger than the
star halo itself
and basically I'm just getting rid of
these brighter star halos
okay and it doesn't look so good
but the point of this was really just to
get some of this outer nebulosity we're
going to come back in and restore detail
to everything in here and in here where
we lost some detail but it's really just
to get this outer nebulosity and then
restore it within a picture where we
have the smaller stars and the way we're
going to do that just as a test here let
me go ahead and move the experiment
layer down one and I'm gonna go ahead
and just take this and actually before I
do that let me fix the background here
cuz this is very reddish and we were
really seeing that gradient again so let
me just go ahead and go back into image
apply image and yeah let's subtract
again this time I'll do an opacity of
say 70 looks good and now I'll just
reset my black point image adjustments
curves take this one and bring it over
here okay so that's good it looks pretty
good for like the outer and a velocity
here and the sky background level is
good again let me just check this
background removal layer that's fine
well actually let me just move the dark
I realized that we haven't done much
with the stretching here because this
was at an earlier stage so let me just
duplicate this one more time I'm gonna
call it initial I'll rename my
experiment outer
Neb okay with my initial I want to go
ahead and open up curves and reset the
black point here and also just bring it
up a little bit something like that I
don't want to stretch this too far so I
want good stars okay but that looks
pretty good and I'm gonna take that
initial and I'm actually going to move
it above the outer nab layer just drag
it up and turn it to the screen blend
mode and what that does is it basically
let me show you before and after so
here's normal blend mode where it's just
showing what's on top here at 100%
opacity if I change it to screen blend
mode any of the darker parts in this
image go to a lower opacity in the outer
Neb but can come through now by doing
that it brought the sort of the overall
black point back up to a light gray so I
would want to get once again open up
curves and apply it but remember every
time we've been doing curves up to this
point it's been just applying to the one
layer we don't want to do that on a
layer that we've blended
because that's going to screw things up
so instead we want to add what's called
an adjustment layer
I think Photoshop added these in like
cs3 or cs4 and so up here right above
the layers panel just choose adjustments
click on the curves adjustment layer and
it comes in here and basically then it
just applies to everything below it so
if you have any blended layers it's also
going to apply to the ones below and I'm
just going to reset my black point here
a little bit there okay so this is
looking pretty cool now but we have one
big problem which is our blown out core
and m43 is even blown out now so to do
deal with that
we need to paste in another stretch I'm
going to go back here to my background
layer and I'm going to duplicate it
and I'm gonna call that duplicate layer
core and I'm gonna take that core and
I'm going to bring it back up all the
way above the curves here and let's just
apply a light stretch to this command L
just the same way we were doing it
before and then I'll just do a little
curves here I'm gonna zoom in I want to
see you know fair amount of detail here
in m43 and in the core but also I don't
want it so dim that it's just gonna look
fake yeah I think something like that
of course this is very red because we
haven't subtracted that background let
so let me do that image apply image
subtract at 70% that's fine
okay okay so now we have just a nice
little layer that's really just focusing
on the core here and what we're gonna do
is basically paint that back into our
crazy blown out version now the problem
is another problem that we have now is
that our crazy blown out version is way
noisier than our core version here which
we haven't stretched as much because
we're bringing out that really really
faint detail here in our crazy stretched
version so what I like to do to sort of
make them mesh a little bit at this
point is apply some noise to
this one I know that sounds crazy to
apply noise but basically it's just
going to help us mesh these two better
some of these things that I'm talking
about are not necessarily best practices
they're really just what we're doing
because we only have 40 minutes of data
here to make it look as good as it can
so anyways go up here to filter we're
gonna go down to noise and click add
noise and basically just play around
with this amount until it looks somewhat
like that layer below unfortunately we
can't see that layer below while we're
doing this but I think something around
7% looks about right there okay you know
fly that add it noise and then I'm gonna
start I'm gonna go back here and just
sort of see where do I have to paint
this in and it's basically this whole
area right there and that right there
and I'm gonna start by adding a layer
mask which is down here at the bottom of
the layers panel it's just a little
white square with a black circle in it
and I'm gonna click that and it adds a
layer mask to this core layer right now
it's completely white meaning that this
is completely showing but if I fill that
mask that it fill with black now we're
seeing nothing in that layer right and
we're seeing just everything below so
then we're gonna start painting in the
core here with a nice soft white brush
so go ahead and go to your brush tool
pick a nice big completely soft round
brush maybe a little bit bigger like
that and turn the opacity way way down
I'm gonna turn it down to 18% make sure
that the mode is set to normal
and you're basically then gonna start
painting in okay and at first is not
gonna look that good even though we're
getting back a lot of the core details
here we have this weird sort of
transitionary period where it's sort of
this mid gray but we're going to go
ahead and duplicate this core layer and
I'm gonna go ahead and turn off the
layer mask here on this one
whoops delete layer mask okay and I mean
I basically brighten up this area in
this one to sort of transition this in
so I'm going to go back here to my
curves do something like that and once
again I'll subtract that redness from it
image apply image okay and I'll again
apply a layer mask turn it black just
edit fill fill with black and again I'm
going to paint with white to transition
in the core okay let me zoom back out
and see how that looks okay it's
starting to look okay decent I'm not
happy with the colors yet they're very
sort of like a pastel - a little too
bright a little - not vibrant enough so
now we're gonna work with some
adjustments our layers panel we want to
keep fairly neat so one thing I do at
this point is probably just group
everything here and you can do command G
I can't do that in the background layer
I'll leave that one alone do command G
on all those and just call this initial
stretch and HDR and then all press let's
see on Mac this is command option shift
e on Windows I think this would be
control option shift e and basically
what this does is it basically just
makes a copy of exactly what you're
seeing on screen but as a new layer and
so I'm going to call this starting point
and we could at this point apply image
adjustments this way to that starting
point layer if you like working that way
that's fine I'm gonna use adjustment
layers just because I feel like they're
a little bit more you know adjustable
and down the line if I change my mind
about something and I'm gonna start by
just doing another curves adjustment
here and resetting my black point a
little bit darker there and also just
bringing this up just a tad
something like that
let's go ahead and add some saturation
to this picture now so go back here to
adjustments got a hue / saturation bring
it up a bit now if you do it too much
you just get this wildly ugly -
saturated picture too little and it just
you know looks sort of boring so you
just sort of don't try to want to fight
find that right amount the other thing
we can do is if this image is looking
just sort of too blue I think I can try
selective color and bring the cyan down
in the reds go to the magentas and bring
up the magenta and the yellow a little
bit and bring down the cyan and what
really works here in the Selective color
is this neutrals thing and you can see
by bringing down the cyan here it really
changes the nebula quite a bit but it
also changes the sky background but we
can reset that in the blacks
so this is maybe a little too much see
just fairly subtle adjustments - eight
plus seven plus three really changed the
appearance here if I turn that off and
on I like that better
I'm gonna go out here into blacks now
though and reset this we need to sign up
a bit there we go okay anyways I'm going
to call this done the only thing we have
left to do is crop off the edges you can
see if i zoom in on the edges here
there's a number of problems with them
this is just a stacking artifact
basically all your pictures are going to
be in a slightly different place in the
sky and so you get this little edge of
fact right here you definitely want to
crop off and then when I was doing that
stuff with removing the background it
also did this weird thing in the corners
so I'm just gonna grab my cropping tool
here and drag in from the corners until
I'm inside of that region where I'm
seeing the stacking artifact and do the
same thing down here at the bottom and
over here on the left
zoom back out looks good hit Enter
except the crop and I'm just gonna look
away from my monitor I'm gonna make this
full screen look back at it and it's
still and now it just seems to me that
it's just a little bit the sky
backgrounds just a little bit too bright
still if you want to try to evaluate
this with numbers you can do it with the
info panel here and this is showing me
that I'm getting an RGB value of
somewhere around
40 30 30 so my sky is a little bit
redder than it is green or blue that's
probably fine but what I ideally want to
bring those numbers like down into the
teens for my sky background so I'm just
going to apply yet another curves
adjustment layer here and one more time
reset my black point which also helps
with bringing down that distracting dust
so that's it we took this from an
initial let me show you let me just go
ahead and open up just what one light
looked like that's just one 30-second
picture we took 70 of those for about 40
minutes of data stacked them with deep
sky stacker and ended up with this
fairly presentable picture of the Ryan
nebula and the Running Man Nebula I hope
you enjoyed this video and if you have
any ideas for future videos please let
me know in the comments and if you want
to watch the version of this using GIMP
just look right below in the description
or if you're interested in picks insight
and see what we can do with that again
just look right in the description below
and you can see how I process this same
image with those programs thanks so much
for watching
