P 119 of the manual says there is an option in the custom
render settings that allows you to choose "Don't recompress
if possible" I can't find this optin but it's one I could
really use.

There are times when I need to crop a few seconds off the
front or back of a shot.

My captures are done using my Matrox card which hardware
encodes with mjpeg compression. Am I right in assuming that
even if I make one change and render using the same
hardware compression, I am losing image quality? If so I
need a way to save with no recompressing but not to save
with no compression which, with my limited knowledge are
different things?????