Get Better Color In Your Digital Images
10 In Camera & In Computer Techniques

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In certain lighting conditions, images can exhibit a strong overall "color cast" or tint, as in this image, made near sunset on a hazy day with a high air pollution level. (Auto white balance.)
Photos © 2003, Peter K. Burian, All Rights Reserved

Just about everyone loves pictures with rich but accurate hues and tones that enhance the subject. We're less impressed with photos that exhibit flat, dull colors or an artificial neon-like dazzle. There's no scientific standard for "correct" color rendition. Still, most folks agree that images should not exhibit an unattractive color "cast": an overall blue or yellow tint, for example. And we often appreciate images with slightly higher color intensity or "saturation" than the original subject.

In some cases, you can achieve very pleasing colors automatically with the default settings of your digital camera. In other situations, it's worth trying the following techniques for making images in the camera and later with ink jet printers to get gorgeous colors that will enhance your subjects and delight your eyes.

With some experience in using the color correction tools in image-editing software, it's possible to improve images that exhibit poor color balance. In this case, I used the "Auto Levels" feature in Photoshop 7.0 and then applied a "+25 Green" factor in "Color Balance" correction to eliminate a strong magenta cast.

Adjust The White Balance
Although most types of illumination appear white to our eyes, the actual color of light can vary significantly. That's why some images may exhibit an unusual color cast: blue when made on overcast days or in deep shade, yellow around sunrise and sunset, and green when sunlight is filtered by foliage. The color of artificial light varies, too. It's green with many fluorescent tubes, orange with household lamps and even stranger colors with sodium vapor or esoteric types of lighting. Our eyes adjust to these color casts and make colors look "right" but photographic materials--especially film--and digital camera sensors do not. But digital does have an advantage.

That advantage is what's known as an automatic white balance system. It's designed to render whites accurately under various types of light. While some cameras have a very reliable auto white balance system, you'll get the most faithful color balance by making your own white balance settings. Most cameras include settings for sunny days, for overcast days, and for use under household "tungsten" lamps and fluorescent lighting. Select the appropriate for the situation, and you should get fairly accurate results, without a strong color tint in your images.

Cameras rarely include a white balance setting for sunrise or sunset or for unusual types of artificial lighting. In order to reduce the risk of a strong color casts under such illumination, some cameras offer a Custom white balance option. Use it as directed by the camera's instruction manual, and this feature allows you to "teach" the camera to render whites as white, regardless of the color of the lighting. When whites are white, all other tones should be quite accurate as well.

Certain subjects benefit from bold, vibrant hues and tones while others look better with more subtle colors. You can achieve any desired effect by employing the techniques discussed in the text.

Calibrate Your Monitor
If the colors that you get in prints are different than the colors displayed by your monitor, you'll need to take an extra step. You'll need to "calibrate" your monitor: change its settings until it provides an accurate display. This calls for adjusting the Adobe Gamma with one of the Photoshop programs. The process is not overly difficult if you get some guidance from instruction packages available from companies such as ColorBat www.colorbat.com. (Price $20)

You may also want to check out the DisplayMate www.displaymate.com software ($70) for monitor calibration. This program provides a series of test patterns and offers advice on what you can do to improve the display image. If you're a very serious print maker who wants highly accurate colors in ink jet prints, consider the sophisticated products such as Monaco EZ Color software (www.monacosys.com) or the Spyder with PhotoCAL system (www.colorvision.com). (Both cost close to $300.)

Use Electronic Flash For Close-Ups
The light from a built-in flash unit is white, or slightly blue. When shooting indoors under artificial lighting, use flash as the primary light source in order to prevent color casts. Because the range of a small flash unit is not great, move in close to your subject: 10 feet or less. With flash, the auto white balance setting should be quite reliable. If the camera includes a white balance setting for flash photography, that should produce an even more accurate color rendition.

After Exposure, Eliminate Color Casts
While it's best to make images with accurate colors, you can also correct your pictures with image-editing software. The various programs, including many versions of Adobe Photoshop, include tools for adjusting color balance. Depending on the software, you'll find options such as Adjust Tint, Color Cast Correction, or Color Balance. Some Photoshop programs include Auto Color Correction and Auto Level options that can sometimes produce the desired effect instantly.

Some color correction tools allow you to adjust the color balance toward a specific color. The software screen provides guidance, suggesting that you increase magenta to eliminate a green cast, increase cyan to correct a yellow color cast, and so on. Other color correction tools require you to select a target: an area of the image that should be pure white, or gray, or black. These work quite well in eliminating a color cast but you may need to try the process a few times. Select a different target in the image for each attempt until you're happy with the results.

If you want to make ink jet prints that are true to the image that you viewed on your computer monitor, start by calibrating the monitor. Using a Photoshop program, convert the image to Adobe RGB (1998) color space, enhance its color rendition, and use the correct printer settings for the paper that you have loaded.

Get Pleasing Color Saturation
Color saturation defines the intensity of colors. A certain tone can be deep and vibrant, like an indigo sky or a stunningly rich crimson maple leaf in autumn. Images with low color saturation include hues and tones that are flat, without any deep colors. Conversely, excessive color intensity produces an artificial cartoon-like effect that's rarely desirable.

Some digital cameras produce low color saturation while others produce very high saturation in their default modes. As well, certain types of light can affect color saturation. Harsh, direct sunlight can cause glare: reflections that "desaturate" colors, making them appear to be washed out. The soft light on a cloudy day generally produces richer colors, with greater saturation.

Some digital cameras include a menu item for color saturation with settings for Low, Normal, and High. For some portraits, you may want to shoot with a low color saturation setting to avoid creating harsh skin tones. You can always increase color saturation later, in image-editing software, with fine control over the exact amount of any adjustment. Avoid the high saturation setting because it may produce excessive saturation that can be very difficult to correct.

Use A Polarizing Filter
If your digital camera accepts filters, consider buying a polarizer to make outdoor images with deeper color saturation. By wiping glare from reflective surfaces, the filter can produce richer blue skies and more intense colors. Rotate the filter to increase or decrease its effect, watching the changes in the camera's LCD monitor. You'll find that the polarizer is most effective when light strikes your subject from the side. If the filter does not seem to have much effect, change your shooting position relative to the sun and try again.

Fine-Tune Color Saturation
After downloading your images to a computer, you may want to slightly increase or decrease color saturation with image-editing software. Experiment with different levels of saturation, using the "cancel" or "step backward" control if you're not happy with a specific effect. After a few tries, you'll find the color saturation level that's just right for a particular image.

Select The Right Color Format
Most digital cameras and scanners make images in a color format or "color space" called "sRGB" that's optimized for viewing on a monitor or for web use (a color space defines the range of colors available for a digital image file). If you're planning to make prints, you'll want to select a different color space option: one that will accurately reflect the range of colors that an ink jet printer can generate.

Many of the recent Adobe Photoshop programs allow you to select "Optimized for Print" or "Adobe RGB (1998)" color space (this option is available in the "Edit" menu, under "Color Settings"). After making that selection, use image-editing software to enhance an image until it looks perfect on the monitor and the printer should reproduce the colors that you see.

Use The Right Printer Settings
For the most reliable color rendition, use the papers made by your printer's manufacturer. Simply select the paper type that you're using--in the printer driver software--to get great colors in your prints. If you want to experiment with an independent brand paper, check the distributor's web site for tips on the suitable printer software settings. Some of those sites also offer free "Custom Color Profiles": software that optimizes color rendition when using their papers with certain ink jet printers. Download and use those Profiles and you should get accurate colors with that brand of paper.

Develop Your Own Standards
As mentioned earlier, there is no "rule" for correct color rendition. Allow your own subjective preference and good taste to be your guide. Remember that certain subjects benefit from bold, vibrant hues and tones while others look better with more subtle colors. Use in camera settings to make images that are quite faithful to the subject, and then rely on image-editing software to adjust both color balance and saturation. This extra effort will pay off, helping you to make images and prints with great visual appeal.

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