Separation Negatives for multiple Colour Work

[jag2x]

Don, I'm unsure if this will help you with color matching, though I do have an idea as how to go about color mathing...(haven't done it myself yet!)

With the Datacolor printfix pro unit, when calibrating it for a certain printer for the inks you have, the application outputs a sheet of "color steps" for all inks. You then match that with the spectrometer. The application then creates an ICC profile for that paper/ink combination (it performs some sort of magical routine to get your colors looking the best they can!, I'm unsure how this transofrmation takes places in the application?).

So using that same process we can go ahead and create our own print out via the tri color gum way. You'd have to capture the "color steps" output digitally to a file, from there you make sep negs. Follow the same steps you'd make a tri color image of the "color step" digital output file. Then analyze with your spectrometer, and creating an overall ICC profile. Thats it!

This ICC profile can then be applied to whatever image via Photoshop, in the "Assign or Converting image to Profile"..
Then do whatever you do to make your tri color gum.

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Is it this straight forward? I have no idea, never tried it. But it makes sense!

 

[donbga]

Don, I'm unsure if this will help you with color matching, though I do have an idea as how to go about color mathing...(haven't done it myself yet!)

With the Datacolor printfix pro unit, when calibrating it for a certain printer for the inks you have, the application outputs a sheet of "color steps"

Hello Jag,

Thanks for the info but I'm very familiar with the print profiling process for inkjet printing as I've done it quite a number of times with several different printers over the years. As I mentioned in my previous post I have a local friend who can generate high quality profiles using the XRite iOne system. I also have another source using XRite software and hardware that I can use to blind check those results if needed.

It's my understanding that Keith is doing something similar with his tri-color gum which he uses to soft proof with. However, he is creating CMY separations in PS and printing negatives with an image setter and then printing in with pigments in seperate layers. So in someways his methods are similar to offset printing. And as I understand offset printing (which is very crude) there still has to be a proofing run to made individual adjustments to each ink lay down to achieve the proper density and color balance of the composite image.

Perhaps it's time for me to pull out my copy Real World Color Management and re-read the sections on CMYK printing.

I certainly hope someone with Real World CMYK printing experience can chime in.

Thanks,

Don