Big Dog

I'm trying to fine-tune my settings in order to produce the best color, and would appreciate any input.

For Color Settings, I've seletected the U.S> Prepress defaults. Color Management Policies are set to "Preserve Embeded Profiles". FYI, I have the Nikon D100, which is set to Nikon's version of Adobe RGB.

My printer is an Epson Stylus Photo 925. Under "Print with Preview", the Print Space is set to Stylus Photo 925, and whatever particular paper I'm using (usually Epson's glossy photo paper). Intent set to perceptual.

I'm finding that if I change the document's source space from the imbedded profile - Nikon Adobe RGB (i.e. choose Convert Profile), to the Color Settings profile - Adobe RGB - I get better colors. Leaving the documents source space as is produces a slight green/blue cast.

Is it recommended (i.e. would it be a good idea) to change the Color Management Policies to "Convert to Working RGB"?

Thanx!
8))

Blinky2004

This is not something specific to just PS CS. It applies just as well to PS 6/7. And in which case, where you said: "Color Management Policies are set to "Preserve Embeded Profiles.", i would probably change that to "Absolute Colormetric". I was just reading about those settings the other day, and the one you've chosen is a "lossy" type scheme of sorts. It tries to make the best image by changing the image to fit a specific colour outline -- which could then alter the way you actually want to image to look.

I can't recall where it was i was reading about these settings. But i think it was in the PS7 HELP! files. I was looking something up for someone else and stumbled across this topic. Have a looksee yourself. That's the best way to decide which mode is right for you. [righton]

Bacardi

I dare to have a different opinion on this matter.
I don't see this as the absolute truth, only as my opinion, ok?

*RGB Working space: Adobe RGB if you intend to print, and your printer does not ask for sRGB like, for example the HP970Cxi. For web: sRGB. (Monitor RGB is different for the mac or WinPC)
*CMYK Working space: US coated if you live in the States, Eurpoean if you live in E.
*Greyscale Working space: for the web use Grey gamma 2.2 if you're on Win, and 1.8 if you're on the mac. For print , choose dotgain. I chose 20%. You may want to try this one out.
*Spot colours only work with print. I chose 20% dot gain.

Dot gain, the amount of growth or shrink of the dots of ink on the carrier, has to be calculated with a densitometre to be exact. 20% is a general guess.

The second part describes what you want PS to do when you try to open a file with a different working space profile, or that isn't colour managed.

Usually there is a reason why this profile is there, so I prefer to keep it. If it is known by Photoshop that is. In that case, I say: preserve, but ask when opening so I can overrule the setting if I want to.

The third part of the settings is about how the colours have to be treated when you tell Photoshop to switch gamut.

Perceptual maintains the overall look of an image. In fact: it matches the white points and adjusts all the other colours to that so tha the file appears to be the same (as good as possible). It is good for photographs. I use it, because I start with LAB scans, and these have to go to Adobe RGB, or sRGB for the web. Relative does not clip colours, so no image detail is lost.

Saturation is good for graphics where the actual colour is not of prime importance (not for logo's for example). It gives easily distinguishable colours, but not exact hues.

Then you have the two colorimetric options. Both use clipping of colours that fall outside the gamut so that, in continuous tone-files like photographs, detail is lost. Absolute matches all the colours it can, and clips the rest, whilst relative also matches the white-point first, and matches the rest if possible, and finally clips the rest.

Black point compensation I have ckecked as it ensures that the black in the file-to-be-converted, and in the converted file are matched. This avoids dark grey instead of real black, or a clogged black mess.

I would suggest that you get a greyscale ramp from your photographic equipment store (an IT8 file is even better, but costs more). This gives you really perfect greys. (if you print it yourself on your deskjet, the grey will consist of little specks of R,G and B.
Take a pic of it under your desired light conditions and open this in PS. This allows you to see whether there really is a cast or not. It strikes me as odd that there is a difference between Nikon't and Adobe's AdobeRGB. If really so, then Nikon must update its software.

retired_paddza

Good breakdown Erik.

As well as usually having a smaller color space than your final output. So if you work in your monitor rgb, you are giving up possible colors that you might have in AdobeRGB or colormatchRGB.

I tend to use relative colormetric and turn OFF color management on the hardware level when I print, but that's just my personal workflow. Relative colormetric seems a good balance between keeping the colors you intended and using the available space of the hardware.

While we're begging to differ.. hehe. Dot gain settings are completely dependant on the output device and you should get that information from your printshop when you build your graphics. There are some averages, but a good print shop should be able to give you a very solid number to work with. Other than that, these don't apply to home printing and the ilk.

The one thing that I would add... make sure you've calibrated your equipment. It doesn't make any difference what profile you're using if your monitor has a lime green color caste to it. Even doing something software like running adobe gamma or colorsync is 100% better than nothing.

$0.02

Bacardi

I agree fully. But there are oh so many offset printers who hardly use a densitometre...then there is the paper, the humidity, the ink, the rubber blanket, etc etc...


Good add-ons, Mindbender!

retired_paddza

There's enough competition out there, that if I couldn't get a good answer as far as something like dot gain or printing methods from a printer, I'd think twice about using that particular printer.

That's very true though... it's hard to tell from printer to printer. Good object lesson for doing research on your print house.