Q: Where is the 18% gray patch on the ColorChecker Passport?

A: Technically speaking, the 4th patch from the white one in the bottom row of the ColorChecker classic is 18% gray. However, it would not be very practical to try to meter off of such a small patch. You would get much better results with the ColorChecker 18% Gray Balance target.

You also can use the exposure patches on the RAW Enhancement Card to check or correct your exposure. Information on this feature is available both in the interactive training video and the PDF documentation under the Help menu in the ColorChecker Passport software.