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Color on computers is a complicated business, given the wide variety and near-infinite combinations of video cards, displays, printers, ink cameras, the many user-adjustable settings on each one, and the age of the equipment.
I can NOT guarantee an exact color match between your product/event/location, my photos, what you see on your computer monitor, and the appearance of your prints. Occasionally, it will seem that I’m not even close!
Here’s why...
The “color” that you see in print, on screen, and of the subject itself, depends on many factors, including:
“Shooting” light color.
The “color” of the lights under which the object will be photographed makes a large impact on the object’s apparent color.
Various light sources produce light of various color. Direct sunlight is measured at about 5200 - 5500 K. “Daylight”, which is the direct light of the sun with the light from a clear blue sky added in, is measured at about 6000 - 6500 K. Typical light bulbs used in the home (sometimes called “tungsten” lighting) have much less blue and a lot more red and yellow, and are measured at about 3100 - 4100 K. Other light sources have various other color temperatures somewhere between 2900 K (very reddish) and 7000 K (blue-white). This color bar is an approximation of the perceived color vs. “color temperature”.
Camera’s rendering of color.
A digital camera’s “white balance” setting (or the type of film used in a film camera) for the lights under which the object will be photographed makes a large impact on the object’s color.
- A digital camera’s automatic white balance tries to make a guess as to the color temperature of the light and will adjust the camera’s color rendering to what it thinks is correct. But note that many digital cameras also have a button where you can choose one of several “preset” white balance options and a “manual” white balance option. This implies that the camera’s auto white balance doesn’t always get it right. Therefore the camera’s choice of white balance, or the manual selection, might not be optimum for the type of lighting.
- A film camera can be loaded with either “Daylight” (aka outdoor, and equally sensitive to all colors) or “Tungsten” (aka indoor, and less sensitive to reds and oranges ) type of film, then add the appropriate color correction filter to the camera’s lens.
The person viewing.
The following is an extract from the GE Lighting “Seeing Color” web page. I recommend that you to read the entire text on the GE Lighting page.
“How we see color depends on the wavelengths emitted by the light source, the wavelengths reflected by the object, the surroundings in which we see the object, and the characteristics of the visual system. Our conception of the color of an object is a constantly changing, highly dynamic process. It depends on what colors surround the object, how long we have been exposed to the scene, what we were looking at before, what we expect to see, and perhaps what we would like to see. Added to that is the fact that about 8% of the male population and about 0.4% of the female population has a color deficiency or is "color blind" to some degree.”
LCD or CRT monitor.
Adjustments - monitor and graphic/video card. On many monitors, there are often adjustments for one or more of brightness, contrast, color (red, green, blue), saturation, color temperature, and more. A computer’s graphics card often has software adjustments for gamma, red, green, blue, etc. Many times, these monitor and graphic card adjustments are either left at the factory settings, or incorrectly adjusted by the user. The result is displayed colors that are very different than the actual colors.
Age-related deterioration of monitor’s display. CRT displays will lose brightness in one or more of the red, green or blue electron beams, resulting in incorrect color. The backlighting of a LCD displays will change color as the monitor ages.
As a very simple test of your monitor, your graphics card, and their adjustments, you should be able to clearly see 10 distinct shades in the greybar ranging from very light grey to pure black, with no color tints. You should be able to see all 8 separate colors in the color bar
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Ambient lighting.
The color and brightness of the ambient light (room light) under which the print, the object, or the monitor are being viewed, greatly influences your perception of print, object, and screen colors.
Lighting environment the viewer just came from. A person’s visual system (your eyes and brain) automatically compensate for the color of the lighting to make you think that what you see is a “true” color, under the current lighting conditions. But if you move to a different ambient lighting, then colors will seem altered for a few minutes, as your eye/brain readjust.
Print vs Screen Color.
- Print color is “subtractive”.
In the “four-color” printing process, Cyan, Magenta, Yellow, and blacK (CMYK) inks are used to produce the various colors. When ambient light falls on a print, each ink absorbs some of the colors in the light, and reflects the rest. The color you will “see” is heavily influenced by the color of the lighting under which you are viewing the print.
- Screen color is “additive”.
A computer monitor creates Red, Green, and Blue (RGB) light to create the various colors. The screen actively emits these colors, then your eye and brain combine them into the various shades and tints of color. “Black” is 0% red, green and blue light, and “White” is 100% of red, green, and blue. But if the screen has ambient light falling on it, then the colors you “see” will be influenced by the color of that ambient light.
The differences in “palette” (the range of colors) that can be created by a printer (CMYK) or a monitor (RGB) means that some colors in one palette are just not possible in the other pallet. It is unlikely that a print will appear to have the exact same color(s) as on screen, unless special, and typically costly, procedures are used to “calibrate” the entire color “chain” from camera to monitor to printer.
- Most highly reflective metallic colors (e.g.: gold, silver, chrome, etc.) are extremely difficult to print in the 4-color (CMYK) process. Often, professional printing companies will use special “spot” color inks to produce these “colors”, and this is just not possible with most inkjet or laser printers. Some thermal wax transfer printers have optional gold- and silver-colored ribbons.
Print color. Many factors affect the color of a print. Some of the factors are:
- Brand of ink - original manufacturer or third party or even a DIY refill.
- Type of ink - dye or pigment.
- Brand of paper - original manufacturer or some other brand.
- Finish of paper - gloss, satin, matte, etc.
- “Color” and “paper” and “quality” settings selected in the printer driver.
- Color profile used by the printer.
- The color of the ambient light falling on the paper.
Two Monitors side-by-side. From the ColorVision web site’s FAQ...
“Visual observation of two monitors sitting side-by-side will never appear to match exactly. Even if they are the same type, make and model, two displays will have subtle differences that are readily discerned in side-by-side comparison, but become negligible when each display is viewed separately.”
I suggest that you read the entire discussion about two monitors side-by-side on the ColorVision web site.
Additional reading. If you have the time and interest in discovering and understanding more about color in your environment, I suggest the excellent overview of color at the General Electric Lighting web site in their Learn About Light series of educational web pages.
revised: June 23, 2007
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