Digital BW, The Print

Hello,

I have a problem scanning a 8x10 negative: Andreas Weidner, a large 
format photographer I adore, has published a book about fine art 
photography that contains both an 8x10 inch negative (BW) and a 
(conventional FB) print of it. The idea is to print the negative and 
compare the result with Andreas' print in order to improve ones 
darkroom skills.

I tried it digitally. I scanned both the negative and positive with 
my brand new Epson 3200 scanner, using Silverfast software. The 
positivescans well, and the printed version of it looks very fine and 
similar to the original. However, if  I try to scan the negative, the 
resulting scan looks terrible. Especially the light parts of the 
negative show strong stripes of different density. Even very 
homogeneous grey fields in the negative do. I have no idea where this 
comes from. I tried to scan my negs (4x5, on a different film), and I 
did not have any problems. I have no idea of the film type of 8x10 
negative.

Any ideas how I can avoid this?

Thanks a lot for your help,
Ernst