Expert: Glen Demers - 6/27/2008

Question
The colors I see on the screen are not what is printing - especially deep reds which look like brown and nothing close to the red I see on the screen.

Answer
Hi Tracy
Your screen is RGB and lit from behind while what you print is CMYK and reflects light, also RGB has a much larger gamut (color space) and you can't match a lot of the bright reds, greens and deep blues with CMYK - that being said - you can get pretty close with some of today's 6 to 8 color printers.
First - calibrate your monitor, there are lots of programs and devices to do this. Once you have a calibrated monitor Photoshop will use that profile for all of it's screen renderings but it's essential that your monitor has it's contrast or gamma reduced to match printed colors and that your grays are neutral (no color cast).
Second - calibrate your printer - see documentation that came with the printer.
Third - either work in a CMYK color space or proof your image in CMYK before printing. A red of 100% Magenta and about 70% Yellow is about the brightest red you can get using CMYK and you add Cyan or Black to make it darker (deeper).
I hope this helps, for a more detailed explanation of CMYK and the color shifts that occur in printing please see this article.
http://www.bestprintingonline.com/cmyk-color.htm
Glen