Re: Digital Camera Profiling
Re: Digital Camera Profiling
- Subject: Re: Digital Camera Profiling
- From: John Gnaegy <email@hidden>
- Date: Tue, 25 Sep 2001 19:29:27 -0700
The process of profiling is aimed at matching colours on
two different surfaces in the same lighting conditions.
Profiling is aimed at describing the behavior of a device. With a
camera, profiling describes the relationship between a color of light
entering the lens and its corresponding value written to the image file,
that's the basic idea. You build a profile that describes the device,
that's "profiling".
If I take a picture of a red apple I don't care what color the apple is
under different lighting conditions, or what Pantone equivalent it is, I
just want to know what it looked like when the picture was taken.
Meaning given some bits in an image file, how can I recreate on another
device (a display) what that apple would have looked like if I had been
looking over the shoulder of the photographer. So, you need two
profiles, one for the camera, one for the display.
The mere fact of
capturing 3-d information in 2-d media, is adding so much complexity
where it comes to colour, that a profile is rendered useless.
That seems to me an exaggeration given that profiling simply describes
the device. If instead you're trying to figure out what objective color
each object in a photo is, what Pantone chip represents that leaf, etc,
then I'd agree yes, that would be a hugely complex task since reflected
light from each object affects its surrounding objects. But that's not
"profiling" in the color management sense of the word.
---
John Gnaegy
email@hidden