Question on calibration...

[Sylvester Graham]

What I understand so far about calibration is that the tones of a print are set to approximately match those seen on the screen from which the print was sent... or vice versa I'm not sure.

But won't each person's system calibrate quite differently? What about in the professional imaging world, is there some sort of standard so when files are swapped between systems each person doesn't see wildly different results? Example, if a lab converts a file to CMYK for commercial printing, doesn't the printer (company) need to see, and reproduce, exactly what the lab saw?


-Alex

[Adam Kavalunas]

I'm no calibration expert, but hardware calibrators such as the Eye One Display 2 which I use, set up your monitor to display images to a "standard". What that standard is, i'm not sure, but if you send your images to be printed, every lab should have their printers profiled. Then you have to get their printer profiles to show you what your image will look like when printed. It doesnt matter what your image looks like on any other computer, if your monitor is calibrated it'll be just fine.

[Gordon Moat]

Not exactly . . . colour management is communicating colour. Ideally the print you want is what you saw at the location, or at the very least how the film rendered the scene. your monitor (any monitor) is only a simulation. Calibration of a monitor only gets it closer to not being far off the result you might get on a print.

So one better choice is to send a hard copy proof with your image files. The other way to do this is for the printing place to send you a proof, which either you or your client could then approve. The best proof is a press proof, but time and budget constraints can limit when that is used. So other proofing choices might be used, probably the worst being a soft proof, often a PDF file.

Commercial printing places should be able to provide a colour profile for sheetfed offset printing, or really any type of printing they can do. If you understand the RGB to CMYK relationship, then you can convert and optimize your image files. Otherwise send them RGB files, and request a hard copy proof. Tagging a colour space to your image files is one way to communicate colour to the print shop, but if all you are using is RGB spaces, then expect some variation from what you saw on the monitor.

What else? There is paper whiteness and brightness to consider. You might set your monitor to assume 100% paper brightness, or a pure white paper. Many more common printing papers are closer to 94 brightness (or less). Papers brighter than 94 often contain optical brightening agents, and those can also affect the whiteness (sometimes slightly blue-ish or cyan). Then there are types of inks to consider, and varnish touch plates, Pantones, et al . . . this could actually become very involved, though the information is out there for those that want/need to learn it.

Anyway, when you get your hard copy print, take that to your monitor, then adjust the monitor to get closer to your printed output. It usually will never look exact, so accept some variation. A good tool for checking your image files is the colour picker (eye dropper) tool in PhotoShop. Using that, you can check the RGB, CMYK, and Total Ink levels (among other things). If you are given a CMYK profile to use, learn to use the Gamut Warning feature, and CMYK preview, to get a rough approximation of your final print. Anyway, hope that makes some sense. Feel free to ask more questions.

Ciao!

Gordon Moat
A G Studio (http://www.allgstudio.com)

[Sylvester Graham]

Hmm, thank you that was a great basic description. I would like to get very involved. Besides this wonderful digital resource, do you know of any books on the subject? What is the subject anyhow, is it pre-press? Or just calibration?

[Sylvester Graham]

Oh, color management is the subject. Dur.

[Gordon Moat]

I have a wall full of books, continue to attend seminars, and basically never really stop learning about this realm. There are several excellent resources, though the Graphic Arts Information Network (http://www.gain.net) is probably one of the best. There is all the SWOP (http://www.swop.org) organization, GRACoL (http://www.gracol.org/) through the IDEA Alliance, and The International Colour Consortium (http://www.color.org). Those are good basic places to start, and all have book resources.

Without knowing specifically what you want to learn, or whether this is a career move for you, it is tougher for me to recommend specific texts or topics. Many of the companies in the industry also put out great texts and books, such as AGFA, Kodak (through Creo, KPG, and GCG), and nearly all the major paper companies. I do some one-on-one tutoring for photographers wanting to learn CMYK, and for some designers that want to expand their printing capabilities and knowledge.

International Paper put out a nice Pocket Pal (http://www.internationalpaper.com/Paper/Paper%20Products/Pocket%20Pal%20Home.html), which contains most of the basic information. Then there are many individuals who put on seminars about colour management, though quite a few only emphasize RGB control, completely missing the important of CMYK control, and ignoring commercial press choices beyond CMYK.

There are also a few fun resources on the internet. Color Matters (http://www.colormatters.com/) is a great website to explore. You might just want to start your exploration through a company called Chromix (http://www.chromix.com/), who have one of the most comprehensive resources and stores anywhere.

Ciao!

Gordon Moat
A G Studio (http://www.allgstudio.com)

[Sylvester Graham]

Yes, I ask because I soon might have the opportunity to do some work for an educational publication. I already work(ed) part time at a high end imaging lab, someplace that does CMYK amongst other things, so I'm getting experience. But it's a busy place and there's not much time for me to learn, I was just wondering if there are any resources I could find to help me learn more about the subject in my own time. And there are, thanks.

[pherold]

For those who would like a really basic analogy to help understand the concept of color management, check out an article called "The Color of Toast" in several places on the net including here: http://www.colorwiki.com/wiki/The_Color_of_Toast

Just to highlight a section of Gordon's excellent description...
If you can get a press profile from your printer, you would install it in your computer, and go through the View > Proof Setup > Custom procedure in Photoshop. This allows you to see the image on your screen as viewed through the printer's profile. In this workflow, it is important to check the "preserve RGB/CMYK numbers" checkbox. IF the printer's profile is good, and your monitor is properly calibrated, you should be able to get pretty close to seeing what your image will look like when printed, and be able to adjust from there.

But of course, as Gordon said - there are always other things that can affect this also!

-Patrick Herold
CHROMiX

[Brian Ellis]

I haven't read it myself but I've seen a lot of recommendations for "Real World Color Management" by Bruce Frazier as a good source of information.

[neil poulsen]

Real World is good. Another that I have is Andrew Rodney's book on Color Management for Photographers.

Calibration and profiling brings a monitor, to the degree possible, within compliance to the ICC standard defined at www.color.org. (Don't bother trying to read it.:D) Use the Photoshop Softproofing tool at VIEW|PROOF_SETUP to approximate the appearance of the print. This assumes that you have good profiles for your printer/paper combination.

There's a lot to color management. One needs a reference to guide them through some of the intricacies.

[Henry Ambrose]

Here is Andrew Rodney's site with lots of great stuff to read.
Start with the first one - "Color Management Primer"

http://www.digitaldog.net/tips/

A great resource for you.