Solutions for Newton's Rings

perkeleellinen · Sep 20, 2010

I've got an LPL C7700 with universal carrier fitted with anti-Newton glass. I get terrible Newton's Rings on Kodak film but not Fuji film. Why?

Here's my experience:

Ektar 35mm - terrible Newton's Rings
Portra 400VC 35mm - a few Rings
Portra 160VC 120 - just one or two Rings

Fuji Reala, 400H, 800Z, Superia 800 & Neopan - no problems at all.

I checked the data sheets and read that Kodak films are very slightly thicker than Fuji (0.001"). Perhaps the problem is with the thicker film in the carrier. Up until now this hasn't been too much of a problem because the solution was simple: avoid Kodak colour films. But 35mm Reala has been cut in the UK and 800Z is on its way out too. I want to try some Kodak films to replace these favourites of mine.

I read this thread: (there was a url link here which no longer exists)
and learned about "Water White coated Denglas" as a possible solution. Unfortunately the firm that makes the stuff has stopped trading. There's a replacement called "MIROGARD® glass":

Dead Link Removed

So, my question from this rather long post, is to ask has anyone used this Mirogard stuff and also what are Glass & Mirror like to deal with? Will they cut the product down to the tiny size I need for my carrier or are they geared up to supply the framing business?

Thanks!

Bob Carnie · Sep 20, 2010

What is the orientation of the newton glass , is it on the bottom or top, are you using one sheet of regular glass?

perkeleellinen said:
I've got an LPL C7700 with universal carrier fitted with anti-Newton glass. I get terrible Newton's Rings on Kodak film but not Fuji film. Why?

Here's my experience:

Ektar 35mm - terrible Newton's Rings
Portra 400VC 35mm - a few Rings
Portra 160VC 120 - just one or two Rings

Fuji Reala, 400H, 800Z, Superia 800 & Neopan - no problems at all.

I checked the data sheets and read that Kodak films are very slightly thinker than Fuji (0.001"). Perhaps the problem is with the thicker film in the carrier. Up until now this hasn't been too much of a problem because the solution was simple: avoid Kodak colour films. But 35mm Reala has been cut in the UK and 800Z is on its way out too. I want to try some Kodak films to replace these favourites of mine.

I read this thread: (there was a url link here which no longer exists)
and learned about "Water White coated Denglas" as a possible solution. Unfortunately the firm that makes the stuff has stopped trading. There's a replacement called "MIROGARD® glass":

Dead Link Removed

So, my question from this rather long post, is to ask has anyone used this Mirogard stuff and also what are Glass & Mirror like to deal with? Will they cut the product down to the tiny size I need for my carrier or are they geared up to supply the framing business?

Thanks!

perkeleellinen · Sep 20, 2010

It's on top (between light source and negative) and I've got regular glass below (between lens and negative).

Bob Carnie · Sep 20, 2010

Can't help you since this is how I arrange the glass as well.

perkeleellinen said:
It's on top (between light source and negative) and I've got regular glass below (between lens and negative).

Jon Shiu · Sep 20, 2010

Also, make sure the dull AN side is the side contacting the film. One thing that might work is to remove the top glass and tape down the film strip. Might be too laborious if you print a lot of negatives.

Jon

Ian Grant · Sep 20, 2010

I tried the anti newton ring glass in my Durst s but didn't like them. I solved the problem by using plan glass at the bottom and a glass-less top mask.

With 35mm I have no problems with both top & bottom being glass-less, but with 120 find that as long as the bottom is glass the negatives stay flat in the Durst's. I don't know about the LPL but my Durst carriers can be adjusted to ensure the negative is held tight.

Ian

perkeleellinen · Sep 20, 2010

The problem I have with going glass-less is that the inserts for the LPL slightly crop the negative. Only about 1mm which maybe not so bad with 120 but with a 35mm negative a 1mm crop is significant. Of course, I could file out the insert, but I don't like that ragged look anymore. There's a firm in Canada which will supply a glassless insert milled larger to include the rebate, but the price is crazy.

Ian Grant · Sep 20, 2010

I made my own 35mm masks for my Durst, but then I was a poor penniless student at the time. It was remarkably easy.

What I hadn't realised was that those masks have been used with two M601's one scrapped the other in storage, and are now used with my M670

Ian

Robert Hale · Oct 3, 2010

Hi Ian,

Interesting. OK on the AC 901 the AN glass ( Durst orginal ) is above the negative ( AN side down ) and the mask is below so far no problems.
The sliding lens carrier is slightly out focus the front side is slightly down so I have pinched the spare 138 base and table and set it on a tilt so everything now focuses to grain right across the image on both diagonals.
Have not found the energy to strip the lens carrier to find out what is going on. Had to build a relay system to turn the AC 901 on and off and control the coloured shutter glasses when the control desk lost its brains. This is software driven via the parallel port on a lap top, the software is kind of neat as it thinks in “f” stops, magenter/yellow, white light or green/blue or best yellow/blue for split grade.

Regards to all

Rob

mrred · Oct 3, 2010

Would the goop those "digi" people use on their scanner glass work here? Sounds like the same problem. Same solution?

Bob-D659 · Oct 4, 2010

Wet mounting negatives in glass carriers has been around for decades, Edwal No-Scratch works well, clean it off with Ronsonol lighter fluid after you are done.

richard ide · Oct 4, 2010

Lighter fluid and good quality paint thinner can be used as well.

tomalophicon · Oct 4, 2010

perkeleellinen said:
The problem I have with going glass-less is that the inserts for the LPL slightly crop the negative. Only about 1mm which maybe not so bad with 120 but with a 35mm negative a 1mm crop is significant. Of course, I could file out the insert, but I don't like that ragged look anymore. There's a firm in Canada which will supply a glassless insert milled larger to include the rebate, but the price is crazy.

You could file it without a ragged edge.

patrickjames · Oct 5, 2010

You don't have to use the ragged edge. One of my setups for my 670 VCCE uses one glass and one mask in the universal carrier. It sounds odd that you would get newton rings from the emulsion side of color neg, but I never print that so I can't speak to it. I hope you solve your problem, and bravo for staying with color in the darkroom!

Solutions for Newton's Rings

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