I noticed that the algorithm tends to choose a lower timerA value then the original minimum even for framerates below 30.
The algorithm depends on the optimization setting:
- low light (for low frame rates): try to increase only timer B
- exact FPS: try to get as close as possible to the exact value; if there are more solutions, the one with smallest timer A is chosen (that results in lowest jello effect)
- high FPS: try to decrease timer B first (no side effect on shutter speed)
- high jello: try to increase timer A first
At extremes, in all cases the algorithm should hit the hard limits for both timers (at least in theory).
On new cameras (including 1100D), timer B can be changed either with
the side effect of altering the shutter speed (you can choose whether you want the side effect, or not). So, low light mode includes the side effect, to get slower shutter speeds, but the other modes will cancel the side effect.
Technical: timer B can be altered via engio (with side effect) or via table patching (without side effect, but requires a video mode change to take effect).