Re: camera profiling
Re: camera profiling
- Subject: Re: camera profiling
- From: Jack Bingham <email@hidden>
- Date: Fri, 28 Sep 2001 12:58:36 -0400
- Organization: Jack Bingham Studio
Jeff Stevenson wrote:
Theoretically, gray balancing a digital camera to the lighting
conditions of the photo shoot should get one to the neutral state from
which the profile was made. This is exactly analagous to what film
photographers do when placing CC filters in front of the lens to correct
available light or an individual emulsion to a known balanced state,
typically daylight or 3200K lighting.The greater the difference between
the light source from which the profile was made and the new light
source, the more work the software (or filters, for film) has to do, and
more deviation is likely.
Also, very often photographers don't want to grey balance, but wish
to preserve the unique look of different conditions such as magic hour
before sunset, etc. At that point the profile should preserve the look
of the lighting compared to the measured profile under controlled
conditions.
I have seen some studio digital back profiles that do indeed function
well with a camera gray balance. From my own perspective working with a
Kodak DCS 660, I have yet to find software that will create a reliable
profile for my device. If anyone out there has been successful with this
chore, please let me know your methodology.
Actually gray balancing a camera is a far more accurate means of color
correction than cc filters could ever be. Gray balancing addresses the
red green and blue channels separately to make them equal on a chosen
color. Filters effect all three colors as a set and therefore can not be
as precise. As far as magic light goes the profile will still work
correctly if you use gray balance the way film does. You need to shoot
using a daylight gray balance, so you either need stored gray balance
settings or some means to correct the gray balance under various
lighting situations. Now if you are trying to reproduce a specific shirt
color under sunset conditions, that's a whole nother matter. If you are
having trouble making a good profile I would suspect gray balance,
lighting setup and camera interference before I would blame software.
Of course some programs work dramatically better than others.