Bringing this to the top with a new question.....
I have TIFF files of GretagMacbeth Color Checkers. They are from
www.basICColor.de and are created from samples of many charts and then saved in different colour spaces.
If I open them in CS5, I can read off the 0-255 values and they are as given, whether in Adobe RGB or sRGB.
Similarly, if I open the sRBG file in LR3, I can read off percentages, which I have made a note of.
My question is this.....
If I correct a Gretag CC in a photograph to match the sRGB/% values that I have noted, and if I then save out the corrected file in Adobe RGB, will the saved file be as if I had been editing in Adobe RGB all along?
Thanks.
D.
Edited: I've pretty much answered my question (I think!
) and in a good way. Here's what I did.....
1. I opened the sRGB Gretag CC in CS5 and assigned the sRGB profile to it. The colour picker values were exactly as I would expect of an sRGB CC.
2. I then saved it as a TIFF.
3. I then opened that sRGB TIFF in LR3 and saved it back out to another location using my LR 3 settings - i.e. 16bit TIFF/ Adobe RGB.
4. I then opened that new TIFF in CS5. The readings were exactly as I would expect of an Adobe RGB Gretag CC.
So, LR 3 is converting the MRGB values it displays to Adobe RGB (or whatever you choose).
Now all I need are % MRGB values for the Gretag CC that I can correct to.
A quick Google brought me to these.......
http://lagemaat.blogspot.com/2008/06/srgb-tone-curve-and-lightroom-color.htmlIf they're OK, then fine. If not, I'd be grateful for another link.
Thanks.
D.
Ps. But, does LR3 have an ACR-type colour picker that allows you to perform a Bruce Fraser type calibration by picking values from the colour patches in a Gretag CC? Coz, if it doesn't.........I've been wasting your time.