Combating anti newton rings

Vincent Brady · Nov 16, 2008

Because I use an XPAN camera and finish up using 24 x 65 mm negs I had my neg plates cut to suit this size. Prior to this I had used glass plates which were great but occasionally give anti-newton rings which spoiled my prints.
However with the new cut plates the ends of the negs appeared unsharp. So lately I changed the top plate back to to the glass insert. Back came the anti-newton ring in my first print.
My latest cure was to cut a piece of thin card and cut an ope for the xpan neg and stick it to the top glass insert. Now I have a glass plate a thin card the neg and the bottom metal plate.
Results : no anti- newton rings on my prints so far .

Cheers
TEX

david b · Nov 16, 2008

I used anti-newton glass with my xpan negs. never a problem.

Ian Grant · Nov 16, 2008

Oxymoron - you can't combat "anti newton rings" that assumes you want them

I always use glass in lower half of my neg carriers and a metal mask in the top, I never suffer fro Newtons rings that way. I've really never liked anti-Newton rings glass.

For my MF negs I either do the same 6x4.5 & 6x6 but for 6x9 & 6x17 I use glassless carriers, but Newton's rings are now hard to get anyway with modern 120 film.

Ian

Maris · Nov 16, 2008

I always use glass in the upper part of the negative carrier. When the heat from the enlarger lamp hits the negative the negative wants to bow upward; the glass stops this and the neg stays flat. I've never seen a neg bow downward in a neg carrier. And leaving the bottom glass out means two fewer surfaces to dust.

Instead of anti-newton glass I use ordinary non-reflective picture framing glass in my negative carriers. Does the subtle texture of the non-reflective glass get imaged on the photographic paper? Yes, if the enlarger uses a point-light source or a highly collimated condenser system. No, it seems, if the enlarger light is diffuse or semi-diffuse.

Vincent Brady · Nov 16, 2008

Thanks David and Ian, despite my "oxymoron" you both knew what I was on about. My enlarger is a Krokus 3 which I bought second hand and I have it for 30 years with the original 75 mm Fujinar-E lens which suits the xpan neg from what I can make out. I will certainly try out your arrangement should the problem reappear Ian. Thank you both.

Cheers
vincent

Martin Aislabie · Nov 17, 2008

I find over the winter in England (and I have no reason not to assume it is also true of other cool damp climates) that even Anti-Newton glass isn't enough to overcome the issue.

I found there is no true cure but there are a few things that help

Glassless Neg carrier - on the top at least

IR Glass in the Enlarger to reduce the likelyhood of Negs "Popping" during exposure

Keeping the darkroom well ventilated to help manage humidity levels

A Normal Hand Help Hair Dryer to pre-warm both the Neg and Neg Carrier

Pick warmer dryer days to print

You could of course install air conditioning in your darkroom and/or move countries to a warmer dryer climate - but it does seem a little over the top

Martin

richard ide · Nov 17, 2008

One method I have used to prevent newton rings is to use an extremely light dusting of rice starch on the glass. I have never noticed image degradation from using this method.

BBarlow690 · Dec 5, 2008

Somebody once told me to breathe on regular glass and wipe it off with a paper towel. I do that for 8x10 contact printing, especially in dry winter months, and have not seen a problem. Could it be a little residual moisture? Beats me, but what works, works.

Combating anti newton rings

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