SCREEN vs. PRINT

Although photographic processing equipment is calibrated, a printed image will look slightly different, in some cases, than the image when viewed on a computer monitor or a phone screen.  It can be more noticeable when there are bright and vibrant colors.  There are two main reasons for this. The first is that screens transmit light and a printed image reflects light.  The second is the color range that can be shown on a screen is greater than the range that can be shown in a print.  The information below covers these two items in more detail.

Computer monitors and phone screens create and emit light using 3 primary colors: red, blue, and green (RGB).  This is an additive system (meaning the 3 lights add together to create various colors) and when all 3 colors of light are transmitted the screen is white.  When no colors are transmitted the screen is black.  When two of the colors are transmitted the screen is yellow, cyan (light blue) or magenta (pink). To get other colors, various levels of each of the 3 colors are transmitted.  Because, the monitor/screen emits light, an image on the screen can produce brighter and more vibrant colors than a print.

Print media reflects light from the environment using 3 primary pigments: cyan (light blue), magenta (pink), and yellow (CMY).  This is a subtractive system of color, meaning colors are taken away as more pigments are added.  A white photo paper is used, so when no pigments are added, the print is white.  When all 3 pigments are added, no light is reflected and the color is black.  Its actually not quite black, so a black pigment is added to the CMY pgiments.  The black is called a "key" and is designated as a "K", so the actual color system is CMYK.  When two of the pigments are added the image is red, green or blue. To get other colors, various levels of each of the 3 pigments are added so that some colors are reflected more and others are reflected less (absorbed).  Because this is a reflective system, a printed image may be less bright and have less vibrant colors when compared to the same image on a screen.

The sRGB or "Standard Red Green Blue" color space was defined by Hewlitt Packard and Microsoft in 1996 to use on monitors, printers and the Internet.  As shown on the chromaticity chart above (yellow triangle), it represents only a small portion of what the human eye is capable of seeing (entire color area).  It does, however, cover a larger area than the CMYK color space particularly with pure primary colors (corners of triangle - red, green, and blue).

The CMYK color system was developed for print material such as photographs or magazines.  As shown in the chromaticity chart above (blue shape), the CMYK color system also only represents a small portion of what the human eye is capable of seeing (entire color area).  It also represents a smaller portion than the sRGB color space which is why prints can sometimes look less vibrant than the same image on the screen.

*Chromaticity chart from Jared Bendis.