Re: Camera profiling with ICC et al
Re: Camera profiling with ICC et al
- Subject: Re: Camera profiling with ICC et al
- From: Uli Zappe <email@hidden>
- Date: Tue, 16 Sep 2008 07:05:10 +0200
Am 16.09.2008 um 04:32 schrieb Graeme Gill:
Uli Zappe wrote:
I don't really understand this. Let's assume a specific profile is
way off with respect to one specific color patch on the target.
Now, it might well happen (and in fact, did happen during my
testing), that a real scene contains an object of exactly this
color. As a result, this "real scene object" will have a wrong
color on the image. How does this not make the profile a "bad"
profile for color accuracy?
Because a cameras spectral sensitivites in general don't match a
human observer spectral sensitivies, metamers to one may well not be
metamers to the other. So there can be colors that appear identical
to the human observer that appear different to the camera. No
uniform color transform can fix this!
Yes, but in my example above, when I wrote "exactly this color", I
meant this in a spectral way.
The colors on a camera target may be an extremely tiny part of all
existing colors, but they still are a part. I.e. it might happen in
"real life" that you encounter exactly (in a spectral sense) one of
the target colors. If on a target one color is way off, we know for
sure that the camera will not be able to reproduce *all* of the
myriads of colors correctly. If no color is off on the target, we
might still hope that we have the "perfect camera". Maybe this
argument is moot from a probability perspective, but in principle it
holds. :-)
Bye
Uli
________________________________________________________
Uli Zappe, Solmsstraße 5, D-65189 Wiesbaden, Germany
http://www.ritual.org
Fon: +49-700-ULIZAPPE
Fax: +49-700-ZAPPEFAX
________________________________________________________
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Colorsync-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden