Accurate Colors in Slides or Photos
by Bob Cherry

Whether you are using your camera to photograph your artwork for juried show submissions or a portfolio, you will want it to match the original.

Different light sources such as sunlight, tungsten photographic lamps, or ordinary incandescent bulbs have different color spectra. This in turn will influence the color balance of your painting when you take slides or photographs. To get an accurate image, match your digital camera settings or film choice to the lighting conditions.

When your film choice or camera settings do not match the available light, your photo will record the color of the light as though your art was tinted that color. You do not notice this yourself because your brain corrects color perception for the effect of different light sources, but film can not. These photos taken with a direct sunlight camera setting show the consequences in a painting that is predominately blue-grey.

With indirect daylight

With incandescent lighting

Regular light bulbs are the worst offender because their color is quite different from the sunlight for which most ordinary films are balanced. The color spectra of tungsten photographers’ lamps and fluorescent bulbs lie between incandescent bulbs and sunlight, while electronic flashes are nearly the same as sunlight. There are also differences between direct sunlight, overcast daylight (bluer), and outdoor shadows or a window-lit room where indirect daylight comes from a (very) blue sky, as in the first photo which is too blue. Consequently, subtle color imbalances are often possible although you may not notice them at the time.

Advanced digital cameras can electronically correct this color problem as the photo is taken. Check your camera’s manual for a discussion of “white balance”. While the default automatic correction might work well, try some test photos with different manual settings to see if the results are more accurate, especially if your color palette is quite warm or cold.. Alternatively, you can manually correct the colors with image processing software before taking the image files to a camera store to be printed as slides.

Film cameras require advance planning to get accurate color reproduction. You should buy film made for the type of lighting you use. This information will be printed on the film box. Daylight film is the most common. For indoor photo studios with artificial lighting, films are available that are color-balanced for the tungsten lamps often used.

It is possible to work with mismatched film and lighting. A screw-on colored filter on the lens can give proper color rendering. (This corresponds to adjusting the electronic white balance on a digital camera.) A blue filter makes incandescent lighting look right in a photo taken with daylight film, while a light yellow filter can adjust indirect sky illumination for direct daylight films. The filter must be matched to the film and lighting you are using and to the diameter of your camera lens as well. Ask at your camera store for help selecting appropriate film or filters and, if necessary, a lighting system.