Image converted from ProPhoto to CMYK questions?

[dgberg]

Never done a thing with CMYK.  All of my printing is through Lightroom using ProPhoto RGB.
I photographed several fine art painted images for digital reproduction.
On our ProPhoto test prints the reds were all over the place as I changed medias and matching profiles.
With all of the vivid reds I did a gamut check in Photoshop.
 Epsons exhibition fibre with pk ink was the only paper that showed all colors 100% in gamut. But still different then the painting.
All of the matte papers proofed showed almost 20% of the reds out of gamut. All these tests were in ProPhoto RGB. Both relative and perceptual.
Having little to no experience with CMYK. Would the conversion help me get a better match especially with the reds?
I tried several prints in CMYK. My first converted print was sort of flat with slightly washed out reds.
Rita Amladi has an excellent article on the subject and suggests Color Match RGB.

What say yee masters of CMYK?

[Randy Carone]

Dan,

You may need a RIP to get good color from a CMYK file. I'm certain that the true experts on LuLa will give you excellent advice on this.

[digitaldog]

I doubt the problem is ProPhoto, certainly alone. Its far more likely either the CMYK profile itself or how you've printed the CMYK data (don't think of sending CMYK through an Epson driver). What makes ColorMatch useful for CMYK conversions is what makes ProPhoto useful in that regard, the 1.8 tone responses curve. But you can try it. I suspect you'll see no real difference over ProPhoto. You have to do an RGB to CMYK back to RGB conversion to print through the Epson driver (using Absolute Colorimetric on the 2nd conversion out of CMYK).

ProPhoto>CMYK>EpsonRGB

[dgberg]

Thanks Randy and Andrew.
This may be easier to just make slight saturation changes to better match the reds instead of bouncing back and forth between RGB and CMYK?

[digitaldog]

Why CMYK in the first place if the only output is Epson?

[dgberg]

Why CMYK in the first place if the only output is Epson?

Yes the only output is Epson.
Not sure where I read it? Maybe PS Cs5 chapter 12 by Martin Evening and Jeff Schewe?
 For better color matching use CMYK?

[Schewe]

Yes the only output is Epson.
Not sure where I read it? Maybe PS Cs5 chapter 12 by Martin Evening and Jeff Schewe?
 For better color matching use CMYK?

I would never have written that...(and neither would Martin)

Epson is a Cc, Mm, Y, LLK, LK, K ink system that expects RGB input data...unless you are trying to do a cross rendered proof of a graphic arts press, you do not want to send CMYK data to an Epson.

As far as a "gamut check" do you mean you checked for out of gamut colors? That's not terrible useful. OOG only tells you it's out of gamut, not what it's gonna look like when printed. Doing any work on the image based on OOG is a fool's errand.

The best bet is to use soft proofing to determine how an image will look when ink hits the paper.

I would look real hard at how you shot the paintings...under what light? Shot with what? How did you process?

[dgberg]

I would never have written that...(and neither would Martin)

Epson is a Cc, Mm, Y, LLK, LK, K ink system that expects RGB input data...unless you are trying to do a cross rendered proof of a graphic arts press, you do not want to send CMYK data to an Epson.

As far as a "gamut check" do you mean you checked for out of gamut colors? That's not terrible useful. OOG only tells you it's out of gamut, not what it's gonna look like when printed. Doing any work on the image based on OOG is a fool's errand.

The best bet is to use soft proofing to determine how an image will look when ink hits the paper.

I would look real hard at how you shot the paintings...under what light? Shot with what? How did you process?

Sorry Jeff thought the proverbial question mark would cover me. I really was not sure where I saw that.
Shot with D2xs and Elinchrom lighting system.
Used EasyBalance Calibration Card to set white balance.
Processed in Lightroom and Cs5 and printed with 7900.

To explain myself further, I was actually checking for out of gamut reds when switching between different paper/profiles.
Epson EEF and PLPP were the only 2 (PK) that had nothing oog.
All of the matte papers showed about 20% oog in the reds. Need matte prints so this is what I am trying to fix.

[Sven W]

Printing strong reds from a painting, to a matte paper, will indeed give everyone headache.
I would start to look for the matte paper with the biggest gamut volume, e.g. Ep Hot Press or BreathingColor Elegance
And your printer is probably the one that gives the "best" reds on the market, with its Vm+LVm+O.

When I know that some of the saturated colors in a painting, never will print "full", I'll skip the saturation part
and look more for the right nuances and luminance.
One thing to cheer up with, is that the original and reproduction never will hang together  

/Sven

[Craig Murphy]

Wouldn't doing a custom camera profile with a color checker for your lighting setup help with this?  I do it and can see color changes in artwork when I apply it in LR.  It would be 1) apply profile then 2) white balance on the color checker.  No?  

[dgberg]

Craig,
I did a custom white balance shooting my 18 percent gray Easy Balance.
Will the color checker and it's software give me any better results if you know?

[Craig Murphy]

I'm referring to a profile for the lighting situation using the Color Checker Passport software. (free I think)  Its not just a white balance.  I shoot a macbeth color checker then run that image through the software to create a custom profile that imports into LR.  Instead of using the Adobe Standard that shows I pick the created profile. 

[dgberg]

Just read up on it,looks like it may help.
Studio work is a sideline I am doing more of lately.
Thanks for the input.

[BobDavid]

If you are using the D2Xs for fine art reproduction the adage garbage in garbage out comes to mind. A Nikon D2Xs is not an appropriate tool for high-fidelity color repro work. It might be able to produce pleasing color, but it was never designed nor intended to be used for fine art reproduction. Decent entry-level digital backs for fine art repro are the Hasselblad 528C or the Sinar 54H. I think those backs were introduced around 2005. I think the Hassey is more flexible and is supported better. If you are shooting still lifes/products in the studio, then disregard the above.

[dgberg]

Bob,
Just an update
I am doing this project for a good friend/client to see how the results come out shot with the equipment I have.
We both know the equipment is not ideal but the plan was to see what kind of quality and color accuracy we get out of what we are using.
Today she took this image to a firm that specializes in reproducing fine art prints.
Am anxious to compare the results from that shoot. Some form of mf digital,not sure what model they use.

[Craig Murphy]

A few years ago If I had had a spare 10k I could have gotten a 54h with a Mamiya 645 and an Apple computer with the Sinar software.  I would love to see some of the artwork I have shot done with the 54h in 16 shot mode.  Pretty amazing that the sensor can move from side to side and up and down one pixel at a time.  Better have a sturdy tripod, consistent lighting and a vibration free floor.