I don't print a TON of my photos, but when I do it's because it's really important to me. I've got a MacBook Pro attached to a Samsung 2300 display and an HP Photosmart 7760 printer. I typically use Lightroom for OSX, but occasionally will make use of Aperture if the mood strikes.
What steps should I take to ensure that my print matches what I see when editing the photo? I've got a monitor calibrator, so I'm using the calibrated display profile. What do I need to do with my printer or Lightroom, though? Should Lightroom, the printer, or something else manage the color profile?
I'm looking at buying a much higher quality printer (Canon Pixma Pro) but want to make sure I know how to get the most out of my prints before I spend any money.
Answer
Calibration
First off, the obvious stuff: Calibrate your monitor, and use appropriate ICC profiles for your printer/ink/papers. You mentioned you already have a calibrated monitor, and for the most part, you should be able to find quality ICC profiles for your printer and the papers you use on the net (I use a Canon PIXMA 9500Pro myself, and make use of a very wide variety of papers...there have only been a couple occasions where I've had to generate my own profile.)
Soft Proofing
Having a calibrated screen and proper printer ICC profiles is a good start, but it is generally not enough alone. To really match what you see in print to what you see on screen, you need to soft proof. Lightroom 4 Beta brings some basic soft proofing tools to the table, however for some of the best, you should really turn to Photoshop. Photoshop has some amazing capabilities when your soft proofing that help you properly match your print to what you see on screen.
Screen/Printer Differences
Even with proper calibration, there are still some fundamental differences between a computer screen and a printer. The most obvious is the fact that screens are luminously transmissive, emitting RGB light, which conforms to the additive color model; conversely, printers are reflective, producing light by reflecting CMYK (and possibly many more) colors from ink on paper, which conforms to the subtractive color model. Because computer screens are transmissive, they tend to have greater dynamic range, and often larger gamut (although the gap is closing these days with special papers and advanced inks.)
The difference in color model and emission can create a visible difference in a print from what you see on screen, even when everything is properly calibrated. Print will generally be duller, and even with the best inks, bright primary and secondary color saturation will rarely reach the same levels as possible on screen. Similarly, maximum black and brightest white are limited by ink formula and density and paper brightness, respectively. With a modern wide-gamut printer like a PIXMA Pro, color gamut correction will probably be less of an issue than white and black point correction.
Correcting for Print
If you want maximum accuracy when you print, there are a few things you can do before hand. First and foremost is to make sure you have the best ICC profile you can find for your printer and paper. Second, make sure you select the right ICM Rendering Intent before printing or soft proofing. Generally, Perceptual will maintain the perception of print-to-screen accuracy, and is probably recommended. If actual-color accuracy is more important than perceptual accuracy, you may want to switch to Relative Colorimetric.
Before printing, you should create a printer, paper and print size specific copy of your photo. Once you have this copy, final and manual resizing and sharpening for the exact print size/border size you want should be performed. You can always leave sizing up to the printer, but the results are usually unpredictable. Save this copy before proceeding to soft proof.
Enable soft proofing in Photoshop, and make sure you choose to adjust black point, simulate paper, and pick the correct ICC print profile and ICM rendering intent. You should see your image change, probably become a bit duller, and be rendered on a different color background that should approximate your paper. If there is a large deviation in the simulated paper vs. your real paper, you might want to try creating an ICC screen profile that improves matching. (Personally, I use the DataColor Spyder Elite, which includes a utility to easily switch color profiles. I have a variety of color profiles that I can switch to with different white points, so I can quickly match my work environment to my paper...or at least get a better match.)
Once in soft proofing mode, the first thing you will want to look at is white and black point. I start with blacks, and use the hot key to enable/disable soft proofing. A fair amount of the time, fine detail in blacks will disappear when soft proofing against a specific print profile. Sometimes, you may see fine black detail is too bright, although its rarer. You can correct this with the levels tool by tweaking the minimum black or black point. Similarly, if you see any highlights that are blown out in soft proof only, you can correct this by using the levels tool to shift white point down. You can actually adjust most settings while soft proofing is enabled, to see the results directly. Any adjustments made while soft proofing will persist, so when soft proofing is disabled, it you'll still see their effects on the image itself.
If you are printing on a paper or with inks that have a particularly limited gamut, you may want to check out of gamut colors as well. You can do this in soft proofing mode, and it will highlight areas of your image in gray that have color values beyond the capabilities of your printer. Generally speaking, if you only see minor spots where gamut is out, and you are using relative colorimetric or perceptual rendering intents, you can leave everything as is...ICM will take care of it all for you. If you see large areas of your print out of gamut, you might want to spend some time either printing test images to see how the out of gamut colors actually render, and if they do render incorrectly, you might want to try correcting them in soft proofing mode. There are a variety of techniques for correcting out of gamut color...I'll leave researching those as an exercise for the reader. The simplest approach is to adjust range-limited saturation down a bit to bring colors back into gamut (although that can have its own side effects.) For the most part, outside of extreme cases, let ICM deal with correcting color for you.
Finally, I highly recommend you make all adjustments using adjustment layers in photoshop, rather than directly. You can always disable them that way, compare differences with various adjustments enabled or not, easily toggle adjustments for different test prints, etc.
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