Outdoor Lighting

With outdoor lighting, it's important that you avoid placing the ColorChecker next to colorful objects that might reflect their color unevenly onto the target. For example, setting the ColorChecker in the grass or next to a bright orange wall would probably not give good results.

It's also a good idea to photograph it on a bright sunny day rather than an overcast and cloudy one.

A good solution would be to have someone hold the ColorChecker at a 45-degree angle between the direct sunlight and your camera.

Studio Lighting

For best results, set up the lighting as if you were performing copy work:

• Two 5000K strobes at 45-degrees on either side of the ColorChecker.
• No direct reflections from lights in the camera.
• Avoid any brightly colored objects that could reflect into the camera.
• Meter the four corners to ensure even lighting.

Tungsten Lighting

A calibration from a target shot under daylight or 5000K will be effective for most of the lighting situations you encounter. However, if you shoot with tungsten, you'll want a separate calibration specifically for tungsten lighting.

The setup is the same as above for studio lighting. With tungsten, be extra careful to ensure that the target is lit evenly.

Exposure

For the most part, the script can operate within a wide range of exposures of the target. However, if you over-expose by too much and the white patches end up clipped, your resulting calibration will suffer. On the other hand, if you under-expose and introduce too much noise in the shadows, the shadow tint adjustment may fail and leave you with a poor calibration as well.

Since you've gone through all the work to properly light the ColorChecker, it's best to bracket your shots as much as possible to ensure that you end up with an image with a proper exposure. Don't rely on your camera's auto exposure. It's best to do this one manually and bracket over a wide exposure range.