Many feel that monitor profiling, soft proofing etc are a bit of a dark art.
People run off prints and the colour differs, the prints look to dark. Its something I have struggled with in the past. If your using monitor profiles to keep your screen accurate, and print profiles, your prints can still be too dark and the colours not as you would expect.
It may be obvious to state but the technology that produces the image on the screen, and that which produces the print are very different. The key difference is that a screen displays by emitted light and has a massive contrast range but limited resolution. A print is views by reflected light, thus has a very compressed contrast, it is this that produces a dark print, our modern screens are way to bright and contrasty.
The other surprising thing for people is that prints are much higher resolution then our screens, thus the image needs sharpening to the point that it looks poor on the screen but great on print.
Because of the differences between screen and print, one needs to post process an image twice, one for screen then again for print.
In fact with the lack of colours available in common web browsers one can even make a case for post processing an image three times, one for screen, one for internet and one for print.
As well as brightness; colour as mentioned above needs considering. The screen displays a difference colour gamut to that of the common web browser, and also print. One cannot say one is better then the other (except for web); the print from modern printers and display a range of colours and a resolution that just cannot be matched by todays screens. But its not as straight forward as that, some colours the screen can do that the printer cannot.
The poor relation is the web. People judging cameras from the web are really missing the point. The web uses sRGB as its colour gamut, this is very limited, and many browsers ignore colour profiling information even when its in embedded in the image, so its impossible to fully know what a image will look like on the web, plus how many users viewing that page have a colour calibrated and profiles display.
Photoshop has for a long time had something called soft proofing, this tries to simulate on the screen what might be on the paper. Lightroom V4 now has this too, and it can be an excellent guide.
I’ll blog some more in the future on how to profile and soft-proof your images but until then, just remember, screen print and web are all very different mediums, you cannot expect your image to look the same.