Proper setting of exposure time for TIScamera

After posting in the TIScamera-forum (http://goo.gl/D8MHsW) I now know
how to correctly set the exposure time of the camera.
Correctly labeling the preview window and generating the title for the
final output window.
Since the ffmpeg-command also takes framerate as input, I'm now trying
to figure out how I can correctly save images from the camera (with a
fan on my desk :).