Using Camera RAW
By: Blair C Howard
Digital cameras typically produce one of two types
of files — JPGs or RAW files. Most amateurs work
with JPGs while most professionals prefer to work
with RAW files.
Here's why:
JPG
files are small and can be handled by most
commercial programs, even those inexpensive ones you
find at Wall Mart and Staples. They are small
because they are created by a process called lossy
compression. This means that some of the original
data is lost, even removed, when the file is created
and compressed. If the level of compression is set
too high it can cause a real deterioration in
image quality (you get to choose the level of
compression both inside your camera - the image
quality setting - and by using a program such as
Photoshop or Photoshop Elements where you will be
able to choose the degree of compression applied to
your corrected image, usually between a range of 1
to 12, 12 being the least amount of compression).
The reason most programs can read and load JPGs is
that they have long been the publishing industry’s
standard format. The JPG is also the standard format
used on the web. So, as you can see, JPG files are
very convenient and easy to use. And yes, they can
be and are reproduced in glossy magazines. One more
thing: each time you save a JPG image you lose a
little more quality until finally the image becomes
virtually useless. As I already mentioned, small JPG
images of less than 100k in size are fine for web
use. A computer screen is set up to handle no more
than 72 dots per inch (no, I'm not going to get into
that here) while publication quality digital images
(for newspapers and glossy magazines) require 300
dots per inch. The JPG file can easily handle both
applications.
But here’s the thing: when your digital camera saves
an image in JPG format all of the in-camera settings
- color balance, color temperature, white balance,
sharpening and so on - are processed by the camera
and placed into the file for you. In essence the
camera says to itself, "this is what I think he/she
would the image to look like, and most of the time
it gets it pretty darned close. And this is not
necessarily a bad thing because you can still change
all of those elements, be it to a somewhat limited
degree, in Photoshop or Photoshop Elements, but when
you do the quality of the image will deteriorate
significantly.
RAW files are created by your camera in a
proprietary format, unique to each camera
manufacturer. They can even be unique to the
specific camera model you are using. These files are
compressed by using a lossyless system. This means
that little or no information is lost during the act
of compression. So, when you shoot a RAW format
file, there will be no in-camera processing. There
will be no sharpening, no color balance applied, no
white balance: the camera has made none of those
decisions for you as it does when it generates a JPG
file. As I said earlier, what you have in a RAW file
is essentially the digital camera's equivalent of a
"negative." No, there is no reversal of the image.
What you have is just an entirely complete original.
And what does all this mean to us? Well, when you
work on a RAW file in Photoshop you are working with
a much higher quality original than you would if it
were a JPG file. You will also have greater control,
which means more creativity, when you make your
adjustments, corrections and manipulations, and you
will not significantly degrade the quality of
resulting image. The first time it will be
compressed is when you save it as a JPG file, or
whatever other file format you choose (such as a TIF).
RAW file formats are unique so we need to use a
special program to process them. All digital camera
manufacturers provide special software for
processing their own RAW files. Often these programs
come free with the camera. The best programs for
dealing with these files, though, are offered as
plug-ins for such industry standards as Adobe
Photoshop or Photoshop Elements.
Another advantage of using the RAW file is that,
other than deleting it, you can’t corrupt it. You
must save the altered image as either a JPG file or
in some other format. Be warned though: always copy
your RAW files to CDs or DVDs for archiving. Then,
as new and more improved processing software becomes
available, you will always have them on hand
whenever you feel the need to work on them again.
About the author: Blair Howard is a professional
photographer and instructor. His published works
include 33 books and more than 630 articlesHe is
also the author of two online, study-at-home courses
for writers & photographers who would like to sell
their work, “The Photo Essay: Getting Your Foot in
the Door,” and Beginning Digital Photography. For
more information:
www.blairhoward.com.
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