Newton Rings and Contact Problems

Contact Issues with polymer photogravure

Newton Rings and Contact problems between the film positive and plate cause these white patches in the print.

Hi Jon,

I’ve been making plates for several years for my photography work and have only recently started having a problem with those dreaded spots on the plate and subsequently the prints.  In researching the problem I came across your web page and it was the ONLY place I have seen a reference to these spots.  I tried you suggestion of drying the transparency and then did a small 4×5 transparency of the image on plate and it seemed okay, but then when I did an 8×10 transparency with the same process, the plate had the dots again.

Do you have any further advice about this problem with Pictorico film?  Or another film that might work without the problem.  It’s maddening and I’ve lost several days of work and lots of plates trying to resolve it with no luck.

I have some Sihl film I’ve never used and considering it.  Anyway, any help you could offer would be very appreciated.  I know Dan Welden and he says it’s a problem with Pictorico.  Is there a work around?

Thanks so much,

Jari Poulin


Hi Jari,

It is much easier to be successful with smaller plates. Larger plates have a learning curve all their own since it is a larger surface area, making tight, contiguous contact with the plate more difficult.

The problem of dark spots (which become white in the print) is typically a contact problem. In some cases it can be attributed to newton rings,. In most cases it is simply a lack of contiguous contact where the film is able to go out of focus and become diffuse in places, weakening the density in the plate in those specific areas.  

Newton rings can occur between the glass of the vacuum frame, and film – or between the film and the plate.  I avoid newton rings on top by using Kreene plastic instead of glass in my vacuum frame.

Two other solutions to avoiding newton rings with larger plates:

1. Pictorico now makes a textured film. The texture creates small cracks where air can escape, avoiding the newton ring issue on some level. 

2. The other solution is to apply baby powder finely to the plate and/or film positive prior to the second exposure to the plate. I use it sparingly, and remove as much as possible with a hake brush before putting in the vacuum frame.  It does the trick.

Hope that helps.  LMK if you have any further questions and best wishes for your project!

Jon Lybrook

Minimizing Dust Specks in Printmaking

For most printmakers, dust is and has historically been the bane of our existence. So much freon has never been released into the atmosphere as from all those cans of DustOff in photographers’ basement darkrooms — when darkrooms were more common. Spritzing negatives in an attempt to get that pristine, perfectly clean negative was one of the most important jobs a darkroom photographer could do.

Now that we’re in the digital age, not much has changed really. Sure, if you’re printing inkjet directly from digital you might be spared — unless there’s dust on the sensor of your camera, but even that can be whisked away in Photoshop, no problem.

For the alternative photography printmaker, however, the physical world is still a very real-world problem. If it’s not humidity causing problems on the East or West Coast United States, it’s dust, like here in Colorado. I have three air purifiers running in the studio where we make polymer photogravure plates. It helps a little, but still dust specks occur and when they do they’re likely to be in some prominent area of the composition like a sky, or the tip of someone’s nose. If it’s in the plate, it’s committed, so you take extra precautions, but what about if it’s in the ink, or dust that lands on the plate just before it is printed?

Here are some precautions to take to minimize dust specks in printmaking environments:

  1. Examine your paper for any specks before tearing and soaking it.
  2. Vacuum and wet-mop the floors and shelves.
  3. Staple plastic above your wiping area and press, if possible.
  4. Keep doors and windows closed.
  5. Keep one or more air purifiers running near your printing area at all times. Make sure they are blowing away from your materials, not at them.
  6. Make sure your rags, tarlatan, and wiping materials have been shaken out and are relatively dust-free.
  7. Examine the plate carefully while wiping to remove any chunks or specks in the ink. Use a clean, lint-free rag to brush off any remaining dust.
  8. Cover the plate with clean tissue paper immediately after examining the plate. Carry it to the press covered.
  9. Use a drafting brush to remove any particles from the printing paper that may have been introduced during soaking or blotting.
  10. Have an assistant remove the tissue carefully just before you put the paper onto the plate.
  11. Clean press bed with anti-static plexiglass cleaner between prints.

Of course, the larger the plate, the more surface area there is to get contaminated. Also the more white-areas there are, the more likely dust will appear there. The less time your plate is exposed to the open air in even a slightly dusty environment, the better chances you have of not introducing unwanted particulates to your prints.

At Intaglio Editions we strive to make photogravure-quality prints that are artifact-free, and that includes digital posterization, newton rings, dust specks and the usual list of pitfalls new printmakers tend to fall prey to. The printing process, whichever it may be, will always lend itself to the final print and influence it in some way. Intaglio printmaking is, after all, an industrial art and along with that comes large equipment, large spaces, and unfortunately, large amounts of dust which invariably, at some point, will work its way into your life, and your prints. I would assert that this very dust issue might be why most vintage photogravure prints tended to be of darker, more complex images, so the dust that does work its way into the prints is not as distracting from the image itself and it simply blends in.  People were also more accepting of it just being part of the process back then as well.