Time system: You can choose one of the following three alternatives for measuring time:
Frames: Time is measured using a frame index.
The number of frames per second can be selected from Animation Settings/FPS control
Realtime: Time is measured with three values: minutes, seconds, frames.
Seconds: Time is measured in seconds.
First frame index: Selects if the first frame index should be zero or one.
For example, in a one hundred frame animation, frame indices run from 0 to 99 (indexing starting from zero) or
from 1 to 100 (indexing from one).