Is there a way to tell photoshop to make the picked areas best fit a set of rgb values ?

[Merlin3]

Hi,

where I need to be able to create an image where the colour I have photographed for research purposes is recreated on screen as best as possible,  I also include in the image a Kodak Q13 colour card  which has blue cyan green yellow red magenta colour blocks as well as a grey surround, angled to avoid flash reflection or other such reflections.

I have rgb values obtained for those kodak Q13 colours., also lab values.

I wish to click the colour blue then tell pshop the rgb target values, ditto the other colours, then tell pshop to best fit the image, adjust exposure, levels, etc .

Else I am am making adjustment to exposure to get the grey value match as best I can, then start adjusting to get blue to best fit the rgb values, whilst still juggling the grey, then adjust the green and now juggling the blue and grey, and..end up juggling so much I drop them !

It would be great to use some best fit command. Is there such ?

Cheers

Merlin

[JJMack]

You can set the picket sample size to get a color closest to that area's color you do not  have to sample a single pixel.

You still get a single color value.  You should most likely add an empty layer on top. Then blend in some color you add to that added layer to adjust the composite image

[Chuck Uebele]

You can use the X-Rite color checker card to make custom color profiles in Camera Raw. I think that would be your best bet.

How to Create ICC Profiles Using the ColorChecker Passport with Adobe CS5

[Norman Sanders]

The Kodak Q-13 is the familiar Color Separation Guide primarily used as a reference for color separation in preparation for print reproduction. The Guide, along with a gray scale, was helpful because a far better technology had not yet arrived. With the introduction of computers that reference card is inadequate. I suggest that, if color accuracy "on screen is as best as possible", you look into the lighting of the subject, your monitor color settings, and the X-Rite Color Checker Passport. The Passport manual in particular will be very helpful.

EDIT: One more reason to steer away from the Q-13 is that, although the grayscale is a photographic print, the Guide is ink-on-paper and over time the color shifts, particularly if the Guide is left out of its envelope. That instability translates to an unreliable reference. Some that I have seen in photographers' studios were downright grungy.