What if I just tape a thicker parcel/multi purpose tape on the glass (or two layers) like a frame so there’s a tiny gap between the negative and the glass when contact printing so it might help avoiding newton rings?
What if I just tape a thicker parcel/multi purpose tape on the glass (or two layers) like a frame so there’s a tiny gap between the negative and the glass when contact printing so it might help avoiding newton rings?
-edited to remove mistaken visualization-
One starts to lose sharpness quickly without firm contact.
Sometimes excessive pressure causes the rings, as does any hint of moisture. Its a physics thing, dang it...some sort of light interference happening between two tightly held-together smooth transparent surfaces.
There is anti-newton glass (a little rough on one side), and I believe there are some sprays one can use on glass to get it to act like anti-newton glass.
Just a wild thought -- have not tried it: There is clear shelf-lining paper with an adhesive backing. I wonder if one covers a sheet of glass with it, the plastic surface might not create newton rings as much (or at all) like the glass surface does.
"Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China
Make the top of the sandwich a diffuse material and the rings go away. Materials such as Satinice and white plexilgass. Also, as Vaughn noted, use any textured material above that touches the top of the negative. And nowadays, altho I have not tried, the coated museum glasses would probably work with coating towards the negative.
I would definitely try this idea! Many years ago, Ron Wisner and I tackled this issue because I was having terrible ring issues at the time. He wound up sending me a single-coated sheet of heavy glass (the same coating used on lens elements, I believe) and, voila, rings gone!
Museum glass works beautifully, but is expensive. I also have some "non-glare" glass for framing which I like.
Last edited by Jim Noel; 28-Feb-2020 at 13:51. Reason: more info
I used to lift up an edge of the glass and set it down just before the exposure. The Newton rings would move around before settling, and this movement eliminate them from visibility in the print. Worked most of the time when making proof prints.
Stick a strip of sticky tape on a piece of glass and give it a test! Perhaps no negative and exposed to light gray...look for any pattern formed under the tape...or do the test with an image.
or
Lay your negative on the photo paper, cover half with your regular glass and the other half with plex and determine if there is any quality difference. Use an image with large areas of even tonality.
"Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China
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