this week I'm gonna have a look at the
uncompressed and compressed raw files
from the Sony a7r 2 and the a 73
on the last few versions of the Sony a
series cameras they've given us the
option of uncompressed and compressed
RAW files I just want to see what the
difference is between these two and if
it's worth having twice the amount of
memory for all of the shots that you
take as a photographer when I hear the
word compressed file I always think of
pixelated small images but what is the
difference between uncompressed and
compressed RAW files from a Sony camera
well for one the size is completely
different the uncompressed file is twice
the size of a compressed file one other
thing to note is that they have a
different raw logo which I didn't
realize until June this video when you
shoot in RAW uncompressed the logo on
the preview file looks like this and
when you shoot a compressed raw file the
logo looks like this if you want to have
a look at the raw files yourself I've
left a link in the description you can
download all of these files and have a
look on your own computer screen and see
if you can spot the difference so let's
have a look at the images and see if
there's any difference at all
so now I've got some images on my
computer as you can see I've got my film
strip along the bottom the red ones are
the compressed ones the green ones are
the uncompressed ones so I've got ones
of Gayo pass in Italy I have some of
some Knights gates and I've got some of
some cityscapes first of all we'll have
a look at Gayo pass these aren't framed
exactly the same there were just some
shots that I've taken on the a7r that
were compressed and the a7 three that
were uncompressed so with the normal
exposure where you get it about right
you don't really notice much difference
I can't tell the difference at all
between these two and these two but
there's not much lick point looking at
those because they're completely
different exposures so let's go on to
the night sky shots I took this shot of
the night sky and these are all on the
a7 3 so this is a 73 uncompressed
this is a 73 compressed when you
actually look at them side-by-side you
don't really notice that much difference
so I overexposed this bed a little bit
and also at 25 millimeters at 15 seconds
I was pushing the boundaries when it
came to the 500 rule so I probably
should have shortened my exposure again
but that's something for a different
video so this is uncompressed and this
is compressed so if we zoom in for two
one
this is uncompressed and this is
compressed now again on four two one
I can't notice the difference saying
that I did expose this correctly for the
night sky so now we're on four to one in
this bottom left-hand corner if I switch
between the two
again I can't really notice that much
difference I'll pull the exposure up a
bit let's go up by one let's go up by
one again the noise patterns look very
similar and the shot looks very similar
so I've got these ones where I included
a bit of the landscape well I've bumped
these ones up by two stops then let's
have a look at the ground they've both
got very similar noise patterns again
there isn't enough light on the ground
to have a proper exposure here so
whatever you do the noise would be there
but you can see between the two the
noise patterns are exactly the same
again if you want to look at these
yourself on your computer and zoom in
and pixel peep as much as you want I
have them in a link in the description
below so with Astro photography and with
normal landscape photography when you
expose it correctly I can't tell the
difference next we're going to have a
look at these cityscapes I bracketed
these because of these bright lights in
these shots so I have my uncompressed
bracketed shots one stop under one stop
over and then I've got my compressed
files this is one stop under and then
one stop over the exposure that I chose
and then what I've done is I've combined
these into a simple HDR image it's a
very basic HDR but I just wanted to see
what the differences were between the
two so this is the uncompressed HDR file
and this is the compressed one so if we
look at them side-by-side you can see
there's still the same amount of detail
in this shot and this is four to one we
switch it to one to one maybe a bit more
chromatic aberration around the edges
but that could be to do with the HDR
process so again with this cityscape
shot I can't really tell the difference
next what I did was a very extreme
bracket I underexposed the shot by four
stops I took a shot this was still
underexposed but then I took a shot four
stops overexposed the reason that the
middle one is a little bit underexposed
is because this one is just clipping
around about here so I didn't want the
whole thing to clip I wanted it just at
the limit so we've got our four stops
over a median shot and then four stops
under now when I balance this out in my
develop module by pushing this one up by
+4 on my exposure scale then I have my
middle shot and then the overexposed
shot which are brought down by minus 4
on the exposure slider the exposures are
very similar and this is where we're
going to start to see a difference so
these three are the uncompressed raw
files and then these three are the
compressed RAW files on the underexposed
shot that really is a difference on the
compressed shot you can see there's
almost a red circle around here and
these buildings are quite red as well on
the uncompressed shot we don't see this
at all so if i zoom in to here I think
this is where we start to see the
difference on the uncompressed shot
we've still got quite a good gradation
in the sky on the compressed shot you
can see this is really red and patchy
you can see it comes around and it
almost follows a circle right in the
middle of the shot altar if we look at
the noise in this part it's pretty bad
in the compressed shot if we were to
bring the exposure up on both of these
then you can really start to see a
difference it's a really strange pattern
but if we switch between the two this is
the uncompressed file and I pushed it
five stops over the exposure that I took
it at and then this is the compressed
one so you can see there's a real
difference with the uncompressed file I
could probably get away with using this
with the compressed file it's rubbish I
wouldn't be able to use this at all with
the shots that I overexposed I've now
brought the exposure on the slider back
up by two stops to give it a bit better
exposure to have a look at the shot
again with these I can't see that much
difference they look very similar as for
these two images that I shared on a
Facebook group I set the challenge to
see if anyone could notice the
difference between the two it was a bit
of a trick question because you have
JPEG compression and then you have
Facebook compression but my point with
these two images on sharing them on the
Facebook group was that you can't
actually tell the difference when you
expose the shot properly when you under
expose the shot a lot that's when you
really see the difference when I first
started out doing this test I thought
there was going to be a stark difference
between the two but I'm really surprised
I thought the uncompressed files would
be so much better
but what I've actually found out is that
unless you severely mess up your
exposure there's not going to be much
difference at all I actually couldn't
notice the difference between the two
shots until I pushed it to that
extremely underexposed shot as I've said
already I've got a link in the
description to all of these RAW files so
if you want to have a look and you want
to pixel peep for yourself download them
and have a look at them and that's about
it I think from now on if I take some
shots where I really have to drop the
exposure because there's some really
bright lights in the shot or there's
parts where I really don't want to blow
out
these ones I'll end up shooting in
uncompressed raw everything else where
I'm shooting where there's good light
I'll switch it to compressed raw and
this'll save me on space
I know memory is cheap but when you're
shooting two to five thousand shots in
one photo shoot space still costs money
now if you've spotted anything in the
raw files or if you've spotted anything
different with your camera leave a
comment below it'll be great to hear
your thoughts as always if you like what
you see give me a thumbs up if you
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