nasty fingerprint type rings on scans

[btaelor]

this is driving me mad.
I'm scanning 120 film @ 4000dpi on a microtek i800 using silverfast
all of the frames I scan have these nasty rings that look somewhat like fingerprints at random areas on the frame.

any ideas what this could be?

here's a sample crop
http://xs319.xs.to/xs319/07363/nastyrings.jpg

x

b.taeor

[pdbolton]

You were close when you refered to them as "nastyrings". What I think they're called is Newton's Rings. I scanned almost a 1000 of my B&W and color negatives & slides and saw the same on most of them. It's a complicated subject to long to put in this thread. If you Google "Newton's Rings", "Scanning & Newton's Rings" or "Newton's Rings on photographic film" you'd get a better explaination of the phenomenon and what may be done about it. Good luck.


Paul D. Bolton
Http://pbase.com/pdbolton

[btaelor]

thanks. i've heard of newton's rings but i didn't know that that's what i was experiencing since they literally look like fingerprints.