Desperately seeking insights

[Mike Lopez]

I'm hoping that someone can give me some advice about a problem that has me beating my head against the wall. I use an outside lab to develop my film (almost always Ilford), and then I make contact prints in my darkroom. I do this with film varying from 35mm up to 6x17. Yes, the 35mm prints are small.

I've encountered some major problems with a large number of 35mm negatives. I've attached a picture I took of some samples during my last print session. These splotches appear seemingly at random, they are arbitrary in shape, and I cannot replicate them from print to print. They appear consistently, but in different shapes and locations on the print.

This does not happen with negatives in larger sizes. I'm consistently able to pull prints from 120 negatives without these problems. It therefore does not seem to me to be a function of the glass or print frame that I'm using. Correct me if that's mistaken, but if I had a fundamental problem with Newton's rings, I would think that they'd show up on negatives in other formats. My problem is with the 35mm negatives exclusively.

Next time I visit the lab I'll quiz them on their workflow between various film formats, but my hunch is that they'll tell me it's all automated, and they won't have any good answers. Can anyone tell me what is happening here? And do you have any advice on how to clean this up to get good prints from these negatives? I have thousands of 35mm negatives that I would like to print without having this garbage appear on them.

Please see the attached, and thank you for whatever advice you may have. This is excruciating, as you might imagine.

 

[MattKing]

Can anyone tell me what is happening here?

Those are Newton rings, and arise because of slightly uneven contact between the non-emulsion side of the film and the glass in your contact printing frame.
Are the negatives sleeved or unsleeved when you make your contact proofs?

 

[Mike Lopez]

Those are Newton rings, and arise because of slightly uneven contact between the non-emulsion side of the film and the glass in your contact printing frame.
Are the negatives sleeved or unsleeved when you make your contact proofs?

The negatives are out of their sleeves when I print. To clarify, these are intended to be final prints--not proofs. Hence the need to eliminate this problem! Do you have any idea why this would occur with my 35mm negatives exclusively? These just don't seem to appear in larger negatives, and I've looked very closely for them.

 

[MattKing]

The substrate that 35mm film is different in subtle ways from the substrate that other format films are on.
In addition, they are small.
Newton's rings are actually interference patterns that arise because of slight variations between the amount of contact between the glass and the negative's surface. Those variations create the same sort of effect that a light sheen of oil on the water creates, with similar colour.
If you have a way of increasing the pressure behind the paper, it may flatten out the negative to glass connection. Is there foam in your contact printing frame, and is it due for replacement?
Another way to deal with the problem would be to replace the glass in your frame with glass that has a slight amount of texture - that breaks up the interference patterns - but the AN glass that is designed for that purpose would be quite expensive in contact frame size.
Newton rings are sometimes a result of low humidity.
One of the traditional ways to deal with Newton rings was to spread a very small amount of very fine corn starch on the glass, but that really only makes sense with large format negatives.

 

[Mike Lopez]

Thank you for your input, Matt. There's no foam in the printing frame to replace. In fact, I've been using this frame for less than a year. I'll try putting some card stock between the paper and the back of the frame.

I run a small dehumidifier in my darkroom when I'm not working in there. I turn it off when I am in there, so that the LED on the dehumidifier doesn't give me problems. Do you think it would help any if I turned it off for a day or two before a print session?

 

[MattKing]

Can you show us the frame, including how it presses the paper against the negative against the glass?
Not knowing where you are, I don't have any sense of whether you need more or less humidity.

 

[RalphLambrecht]

I'm hoping that someone can give me some advice about a problem that has me beating my head against the wall. I use an outside lab to develop my film (almost always Ilford), and then I make contact prints in my darkroom. I do this with film varying from 35mm up to 6x17. Yes, the 35mm prints are small.

I've encountered some major problems with a large number of 35mm negatives. I've attached a picture I took of some samples during my last print session. These splotches appear seemingly at random, they are arbitrary in shape, and I cannot replicate them from print to print. They appear consistently, but in different shapes and locations on the print.

This does not happen with negatives in larger sizes. I'm consistently able to pull prints from 120 negatives without these problems. It therefore does not seem to me to be a function of the glass or print frame that I'm using. Correct me if that's mistaken, but if I had a fundamental problem with Newton's rings, I would think that they'd show up on negatives in other formats. My problem is with the 35mm negatives exclusively.

Next time I visit the lab I'll quiz them on their workflow between various film formats, but my hunch is that they'll tell me it's all automated, and they won't have any good answers. Can anyone tell me what is happening here? And do you have any advice on how to clean this up to get good prints from these negatives? I have thousands of 35mm negatives that I would like to print without having this garbage appear on them.

Please see the attached, and thank you for whatever advice you may have. This is excruciating, as you might imagine.

View attachment 268253

as others said already. This has nothing to do with the lab. You need to use antiNewton glass in your workflow and this will take care of it!

 

[Mike Lopez]

Status update: I spent most of the day printing. I started with some medium format negatives, hoping to build a little momentum (mostly psychological). After a handful of those (with no problems), I moved on to some 35mm negatives. This time I inserted a second pane of glass behind the paper (between the paper and the back of the frame.) This nearly took care of the problem completely. I think that the added (stiff) layer acted to further tighten the clamping action on the paper and negative. Unfortunately I did still turn up some Newton's rings near the end of the session. Very curiously, I finally attempted to print that particular negative on paper that was cut for larger negatives (in other words, I printed a 35mm negative on a piece of paper about 3" square). When I did that, the rings went away and I was finally able to get prints from that negative. This is going to turn into a science experiment.

Thank you all for the input.

 

[koraks]

If no AN glass is available, there's something you can try, but its messy, so I don't really like it. But you can dust the negatives (shiny / back side) lightly with very fine talcum powder before you put the glass on. The obvious drawback is that you have to clean the film properly afterwards, but as long as nothing gets wet/moist, talcum powder wipes off pretty easily. Still, I consider this really as a last resort / very suboptimal solution.

 

[bernard_L]

AN glass is expensive, esp. in a size for a contact sheet. Go to a framing supplies shop, and ask for "anti-reflection" glass (not museum glass). Actually slightly frosted. Being before the negative on the light path, it will not affect the sharpness of your contact print. Usually the slight frosting is on both sides, but I've seen some frosted only one side; in which case make sure the frosted side is the one in contact with the negatives' back side. Weigh down the glass to make sure the paper below is flat.

 

[Tel]

I had a similar problem scanning 8x10 negs on my flatbed. I went to a local glass shop (they sell a lot of framing glass as well as window glass) and began to explain my problem. Before I'd finished the owner had pulled out a piece of lightly frosted glass (as described above) and she gave it to me. It works perfectly.