Reikan FoCal is not very known by DSLR users, so what is it all about? Copied from their info:
So what exactly is FoCal?
FoCal is computer software you install on a PC or Mac, and a special target you attach to a wall. You connect your camera to the PC with the standard USB cable and start the software.
FoCal guides you through the correct positioning of the camera and target, then you can run any of the tools at the touch of a button.
FoCal works with Canon and Nikon DSLR cameras that support AF Microadjustment/Fine Tune – see the Supported Cameras page for more details.