This issue's article on autofocus includes instructions on how to test your camera's autofocus system using author Ralph Altmann's custom animated GIF. The test can be performed on a computer monitor or using a printed version of the test image and the results analyzed using Ralph's custom Photoshop Actions. These can be applied to your own test shots or the sample shots provided here.

This issue's lens test takes a close look at 70-200mm zooms with constant maximum apertures for DSLR and mirrorless system cameras. We checked out camera manufacturers' own-brand lenses and compared them with the third-party competition from Tamron, Sigma and Tokina. This archive contains the high-resolution JPG and RAW test shots we captured.