Practical_Photoshop__Issue_77__August_2017

WHITE BALANCE:
HOW DO RAWS
AND JPEGS HOLD
UP TO COLOR
FIXES?
Shoot raw and, because the
raw color data is recorded,
you can change the white
balance after the fact. Here
our initial image was shot
in Raw+JPEG and set to
Tungsten white balance,
which has resulted in an
unnatural blue cast. Then
both versions were fixed
by clicking on a neutral grey
point (in this case, the white
vest) using the White Balance
tool in Camera Raw. (This can
also be done in Lightroom,
or with Photoshop’s Curves/
Levels midpoint eyedropper.)
The fixed raw gives more
of a natural balance between
the warm skin tones and
the blues and
greens in the
background,
while the JPEG
fix has left
the balance
slightly awry,
with neither skin
nor background
entirely accurate.
BEFORE
JPEG FIXED
RAW FIXED
WHEN TO USE
RAW AND JPEG
Many SLRs and CSCs have
a Raw+JPEG setting that lets you
record both file formats at once.
If you’re happy to accept the extra
memory card space the second
file will occupy, it gives you the
best of both worlds. The raw file
will hold all the original color info,
so you can archive it with the
knowledge that you can always go back to it. But if you’re satisfied with the look of
the JPEG, there’s no need to bother processing the raw. It’s also useful when you need
a quick turnaround on a set of images, as you can quickly access the JPEGs.
JPEG FILE
COMPRESSION:
HOW BAD IS IT
REALLY?
JPEGs are a lossy format,
meaning there’s an
incremental loss of data
every time you open and
save a file. If you only open
each file once or twice, this
is probably acceptable – but
any more and you’ll notice
a drop in quality, especially
in areas of soft gradation
like blue skies. How much
should you worry about it?
Saved once
Our original raw image was
processed in Camera Raw,
then saved as a JPEG. There’s
no noticeable loss in quality,
and so there’s no need to
worry about compression.
Saved 10 times
Now we’ve opened and resaved
the image 10 times
in Photoshop, using the
highest Quality setting. The
repeated compression has
caused banding in the sky.
Saved 50 times
Granted, not many images
will be re-saved 50 times
over, but it highlights the
huge drop in quality. Despite
the drop, the actual file size
has increased from an initial
17MB to 18.3MB.