Newton rings ......... :-((

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I am sure this has been asked many times ... how do I get rid of Newton rings. I have so far worked only with glas carriers. Perhaps get rid of the glass carrier?

-- Klaus Werner (kwerner@zetnet.co.uk), February 03, 1998

Answers

1. Most glass carriers have anti-newton ring glass for the back side of the negative. I think anti-newton glass is available commercially. 2. Is your glass clean? residues, especially soap, can cause rings. 3. Newton rings formation can be increased with higher humidity and residual film wetting agent. I recommend that you use a distilled water rinse for the final washing step of your negatives. When I have been overly anxious to print from a negative that has just been processed and appears dried, I have experienced Newton rings. If the same negative drys overnight, I don't experience the rings.

-- Eilert Anders (eilert@dav.com), February 04, 1998.

Klaus, what kind of glass carrier are you using?

-- Eilert Anders (eilert@dav.com), February 05, 1998.

The glass carriers I have been using appear to be ordinary glass (both sides & top side only). I currently use the facilities of a local arts centre. It's a big darkroom, with 10 (mainly old) enlargers (Krokus, Opemus) and a damp atmosphere.

-- Klaus Werner (kwerner@zetnet.co.uk), February 06, 1998.

For years I have battled Newton rings, trying every conceivable remedy. Here's what has worked best: Anti-Newton glass is available for any enlarger from Focal Point Ind. Inc. 2867 Stonewall Place #101, Sanford, Florida 32773. You only need to order the top sheet of glass- be sure to place the etched side against your negative. This glass will hide Newton's rings very well, but not eliminate them. Increasing the pressure of the glass against the negative will eliminate some but not all of the rings; using the etched glass will significantly reduce those that remain. The only way to absolutely eliminate Newton Rings is to use a glass-free carrier and tape your neg for flatness, if necessary. After years of trying every suggestion I was given, I am getting acceptable results using the etched glass from Focal Point, along with new pressure clips on my Durst carrier. The rings are still there if you really hunt for them, but they are so faint that they don't bother me.

-- Joel Pickford (pickimage@csufresno.edu), March 16, 1998.

There is such a thing as anti-Newton ring powder. I used it years ago, when I worked in photo labs in NYC, but I don't remeber where I got it. You use very little so spotting isn't too much of a problem. I believe it's made from powdered glass.

-- Peter Hughes (leonine@redshift.com), September 20, 1998.


Response to Newton rings

I use an old enlarger with an ordinary glass-carrier, no anti-Newton glass. But the problems with Newton-rings suddenly stopped, and I couldn't understand why, though I was happy about it. The, last week I read that Newton rings are more likely to appear with thin-emulsion films, especially Tmax. I then realised that my Newton rings stopped appearing when I switched from Tmax to the old Tri-X emulsion, which is thicker. So, I for one do not doubt that there is some truth in the explanation that Newton rings can be avoided by using films with thicker emulsions.

-- Peter Olsson (Peter.Olsson@sb.luth.se), November 20, 1998.

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