Q: What are test targets used for?

Q: "What are test targets used for?"

Test targets are used for a few reasons:

  1. To calibrate the input device. When a target is captured, the device looks at the results and makes adjustments to calibration files to get the device to perform-to-spec.
  2. To create color profiles. This process is usually separate from the calibration of the input device (see above). In some cases the input device manufacturer will set up the calibration to use the same chart. Often the color profile (CMM file) is made by another independent software company (GretagMacbeth or X-Rite are two providers). This step is used to create a profile that will tell other applications how to deal with the information found in the color-managed digital file. Often the profile is only used until the image is converted to a more common/generic color space like AdobeRGB 1998 or ProPhotoRGB.
  3. To evaluate and monitor the input device. Some charts have resolution targets, gray patches, and other devices that allow you to evaluate the actual resolution achieved and whether there are any tone or color problems. This can be used to determine if the device is in focus or the file is not interpolated, and to check tone and color balance.
  4. As a visual reference. When used with a grayscale or color bars Q14 can be a tool to determine whether or not there have been modifications to the digital image. (A good grayscale is preferred for this as the Q14 is specific to a printing press workflow.) This can also be used to make adjustments to the image, but should not be considered the primary tool.