The Pentax K-3 uses an innovative system for simulating the effect of a physical anti-aliasing filter.
Pentax has released new firmware for its flagship K-3 DSLR, allowing users to bracket exposures by AA filter simulation mode. As a reminder, the K-3 lacks a physical anti-aliasing filter, but simulates the blurring effect via minute movement of its sensor, with two intensity levels available (three if you include 'off'). Firmware v1.02 allows you to shoot a burst of sequential images at each AA filter level, to fine-tune the optimal balance between resolution and artifacts like moiré.
The update also includes the usual minor fixes and 'stability improvements' - see notes below.