Mount the SpyderCHECKR / SpyderCHECKR 24, or place in a stable location. Light it from a 45-degree angle. The ideal way to light a target is to use a single light source, with no reflector or diffusor, from a long distance. This assures that all portions of the target will have the same amount and color temperature of light. This reduces fall-off and color variation across the width of a target. Don't fill up the fill the entire viewfinder with the target since distortion, vignetting, and sensor dust are worst at the corners. It’s best to photograph the target with a generous amount of border and crop it down in your editing software. The target should be as close to parallel to the camera’s sensor as possible. Make sure the camera is directly in front of the target. Look closely at the shape the target makes: if the rectangle is wider at the top or bottom, or taller at one end than the other, you are not squarely in front of the target. A tripod can be useful. Autofocus produces excellent results. Fully Automatic settings are fine though Aperture Priority or full Manual settings are also good for those who are comfortable using them. It is important to photograph the target in the camera's RAW format, if it offers one. Take a few frames at different settings, if you are unsure of any of the variables.