Flattening negatives for Epson 2450?

[plbh]

I wonder if anyone has advice on flattening old Plus-X negatives for scanning. The film is from 1970 and so curled I have trouble keeping the strips in the holder. If I put it in the "correct" way (convex base side down), the film can hit the glass and cause moire-like Newton rings. (I now scan it upside down and flip it in PS.) The 2450 is a flatbed scanner with a built-in transparency adapter. Some of the scans are here:

http://www.pbase.com/plbh/flores_1970

[stormseye]

I had similar trouble with color 35mm negs. Ultimately, the only thing that helped was decidedly low-tech: flatten them under big heavy books, let them sit for days, even weeks. They should be better (but they probably still won't be perfect).

Finally a use for Janson's History of Art.

[europanorama]

best would be to forget that scanner and buying 4990. results comparing 2450 with 4990 are like day and night.then buy eighter dough fishers mf-filmholder with antinewton-glass or even julio fernandez scanmax-wet-scan-holder 5x7. check his discussion list at:
http://groups.yahoo.com/group/SCANMAX/
discussion about scanning, epson scanner and scanmax-holder.
if registered, go to the files and check the scan-examples and tips. you will be surprised.

[stormseye]

Hey Peter:

Not sure if you've had any luck yet, but I have found that humidity levels make all the difference. Dry = curls, humid = flat. Try keeping your negatives in a different location. I've had mine in the basement for several months now and they have all returned to flatness.