filmscanners: Nikon LS-30 Coolscan III makes scratches on negatives

[Walter Nowotny]

Using the Coolscan III for scanning negatives I sometimes notice scratches
after the scan. Sometimes when I scan negatives with 4 pictures, the next to
the last one gets scratched in longitudinal direction. I thought that these
scratches are caused by extremely bent negatives. Unfortunately the LS-30 is
not long enough, so the negatives are bent and rolled up at the end of the
scanning unit. The turn round is made by some plastics parts which probably
cause the scratches when the negatives are bent too much. I was satisfied
with that explanation and tried to smooth down the negatives before
scanning. However, processing the last two films I noticed straight
scratches across the whole film strip.
Does anyone have the same problems? Or even an explanation and cure?
I would really appreciate! I am tired of ruining all my films ;-)

Thanks!
Regards, Walter Nowotny (Vienna)