I hope kjsphoto's troubles are cured. I installed a non-glare glass in his frame and, at least on my workbench, the Newton's rings were much less apparent. I'd like to write a little article for my web site on this topic, but I admit I have only this minimum personal experience to go on. Maybe I just never noticed, because now that I'm tuned in to it, I see the pesky little patterns on every frame and negative I take the time to closely inspect. I'd like to hear from anyone who has had trouble printing due to Newton's rings. Where, in the print, are the effects most noticeable? (highlights, midtones, shadows). Are certain films less apt to produce the effect? I wouldn't expect the chemistry to have any bearing since it's the film base side adjacent to the glass, but you never know. What remedies have shown the best results?
Tmax films have some trouble with Newton rings, due to their smooth non-emulsion side. AN-glass is normally mounted on the top of the glass-negative sandwich, because the emulsion side is pointing towards the baseboard.
My big question has always been why don't Newton's Rings obey the laws of gravity and fall off the print, like an apple from a tree? ;)
I observe Newton rings pretty much all the time during contact printing sessions. I have yet to see any negative effects on my prints and so I just ignore them. I would also like to hear from anyone who has had trouble in the print highlights, midtones, etc.
Well that is why it came up for me. I never had an issue with them before but I printed a negative that had a lot of sky (white and clouds) and that is where they showed up. I have not tried the frame with the new glass yet but I am hoping to give it a spin this weekend and looking forward as I miss the darkroom :)
Dan, thank you again so much for everything!
A true professional in every regard! And excellent craftsmanship!
Anyway I will let you all know how the glass works this weekend if I am able…
Its really odd how some people get rings, and others don´t. Ive been printing with my negative between glass for several years now. When I make enlargments, I place the negative between two sheets of glass as my negative carrier, and when I am contact printing, I use various types of cheep picture frame glass in my contact frames. I´ve NEVER had rings appear!
Now that I mention this however....they will probably start showing up the next time I print! :-P
I just saw this thread, hope I'm not too late to post -
I have continuing problems with NR, in contact printing (with an enlarger, with a piece of foam and glass, enlarger up at about 11x14 size on enlarging paper.) All from 4x5 negs.
I have tried:
1/4" plate glass, window glass, AntiGlare glass, with the enlarger lens in focus, way out of focus, with no lens (raw enlarge light), with a layer of diffusion material on top of the glass, winter, summer (different humidity levels). I even tried the Ed Weston method - ceiling light exposed manually. I have not made one print without NR's. They can appear in any tonal area, and I can see them during exposure. I finally gave up. Any suggestions would be welcomed.
BTW - In the 70's I did a lot of contacting (the same way, with the enlarger and 1/4" plate glass) with never a problem, in a different darkroom in a different part of Virginia. The only difference that I can think of was that that darkroom (in a university) was perpetually air conditioned (or heated). My new darkroom is in my basement, but I have a dehumidifier going all the time (50%RH).
Try to get a piece of anti glare glass. I think that is what it is. That completely cleared up my Newton ring problems. PM Dan Pelland and ask him. He is an APUG member and makes some of the best contact frames around.
Looks like George was pretty close. If you are contact printing and don't need to see the neg well and can tolerate increased exposure, put the neg under a diffusion material directly. An example of this would be to use white plexiglass directly above the neg (between the neg and the light source). This gives a relatively good amount of diffusion. I don't think Newton can make his little rings in diffuse light.
The same thing works with diffusion enlarging and coldlight. Make the diffusor the top part of a 'glass' neg holder. The bottom can be regular glass.
I can't begin to tell you how thrilled I am today!!!
Finally I solved my Newton Ring problems. I was using a newly made vacuum frame, and the Newton Rings became very noticeable in the mid-tones. Highlights and shadows were not much of a problem. I priced anti-glare glass, but it was far too expensive for me (11x14 $65)...
I decided to try a piece of frosted glass (24x25 $34), and it worked fantastic. The Newton Rings are not merely diminished, they are completely gone now. The side of the glass which is frosted adds a slight texture, and also defuses light evenly, so it was perfect for my purposes.
Now I can get back to printing my photos, and get out and take some new ones!