Newton's Rings

[Sal Santamaura]

...Perhaps you use dry gas heat during winter?...

Since Drew claims I'm on his ignore list, he probably won't see this reply, but here goes anyway.

What the hell is "dry gas heat?" A heating device fueled by the alcohol-based stuff used to get water out of gasoline? Or an attempt at denigrating forced hot air heating systems?

No matter the source, any space heating system that raises indoor air temperature a given number of degrees above outdoor air temperature will lower the relative humidity an amount identical to what other heating systems would. How much lower is easily calculated using this Web site:

http://www.dpcalc.org/

To be sure, forced hot air heat has drawbacks compared to better approaches (hydronic radiant being best), but "dryness" isn't one of them.

[Michael R]

Yeah I remember when I first experimented with Acros and saw that it had a shiny emulsion coat like TMax I was a little bummed. PE hinted that at least in the case of the Kodak films this was by design rather than an unavoidable thing. Anyway.

I’m still a little surprised you’d have found Delta 100 to be problematic with respect to Newton rings forming on the emulsion side. The emulsion “sheen” is fairly conventional, not nearly as shiny as TMax. But I can’t argue with what you’ve experienced.

Depends what you mean by "normally", Michael. Perhaps you use dry gas heat during winter? I duuno. I use only passive electric in the darkroom, and other than Fall, and not even this Fall, this year, the climate is generally damp and foggy, so both side AN glass is essential for me year-round on all my enlargers. But yes indeed, ACROS seems even more slick than TMax. Older thicker-emulsion films did have deliberate retouching tooth on them. And just last week I did fix-out some old sheet film for potential AN usage relative to a spare registered pin glass with a plain rather than AN surface. Worth trying at least. Ordinarily I use thin frosted mylar for that purpose if needed, generally for masking or masked contact internegs etc. But I'm always fooling around with new ideas too, so what the heck.

But I found things like coated Tru-Vue glass or Denglas worthless here. There was a very unusual custom coated Zeiss glass, no doubt surplus from some unlabeled purpose long ago, which I used for awhile in my 8x10 cold light enlarger; but even that wasn't adequate with Acros sheet film, so I switched that carrier to ScanTech AN instead.

One thing which does help is developing film to the contrast level needed in advance. If you significantly boost contrast with a higher grade VC setting afterwards, then both rings and any Anti-Newton texture pattern on the glass inherently become more apparent in the print itself.

[Drew Wiley]

Rings are the rule rather than the exception around here due to the nearly year-round coastal fog, unless one of the very few old school emulsions are involved which still has a viable retouching tooth. True thick emulsion films are long gone. HP5 is OK, and among color films, the new scan-improvement coating of Portra and Ektar sheets helps a bit.

And like I already hinted, I don't use any forced-air heating in the lab. Not only does that up the ante in filtration expectations, and increase static in the air, but dries out and irritates my respiratory system as well. I've just replaced the furnace filters in our house, cleaned the ducts etc, and we do need to use some gas heat for economical reasons in there. But the lab is an entirely different building, where I use passive (radiator-style) electrical heat exclusively. The film room per se is relatively small and with especially thick R23 insulation, so especially easy to keep comfortable in cold weather. It's also where my smaller enlargers are located, meaning anything capable of standing beneath an ordinary 8 ft tall ceiling, including the Durst 138 and its colorhead. The much taller 8x10 color enlargers are in a different room with a high ceiling, and just by being in use those big halogen colorheads warm things up pretty fast. And the mounting and retouching room has a huge drymount press in that - no supplemental heater needed there, though there is one, just in case.

But Sir Isaac Newton has been my perpetual foe ever since I began printing. So I have to resort to every trick in the book, it seems, to defeat him. Maybe I can entice him to invade Montreal instead.

[Michael R]

Don’t get me wrong he invades here too, but not specifically with Delta 100 in my experience. I’ve had to go down all the Newton ring rabbit holes for TMax and other stuff so I can relate. It’s annoying.

Rings are the rule rather than the exception around here due to the nearly year-round coastal fog, unless one of the very few old school emulsions are involved which still has a viable retouching tooth. True thick emulsion films are long gone. HP5 is OK, and among color films, the new scan-improvement coating of Portra and Ektar sheets helps a bit.

And like I already hinted, I don't use any forced-air heating in the lab. Not only does that up the ante in filtration expectations, and increase static in the air, but dries out and irritates my respiratory system as well. I've just replaced the furnace filters in our house, cleaned the ducts etc, and we do need to use some gas heat for economical reasons in there. But the lab is an entirely different building, where I use passive (radiator-style) electrical heat exclusively. The film room per se is relatively small and with especially thick R23 insulation, so especially easy to keep comfortable in cold weather. It's also where my smaller enlargers are located, meaning anything capable of standing beneath an ordinary 8 ft tall ceiling, including the Durst 138 and its colorhead. The much taller 8x10 color enlargers are in a different room with a high ceiling, and just by being in use those big halogen colorheads warm things up pretty fast. And the mounting and retouching room has a huge drymount press in that - no supplemental heater needed there, though there is one, just in case.

But Sir Isaac Newton has been my perpetual foe ever since I began printing. So I have to resort to every trick in the book, it seems, to defeat him. Maybe I can entice him to invade Montreal instead.

[Drew Wiley]

My biggest disappointment in that respect was when second-generation FP4 (the plus version) came out slicker than the original flavor. Neither are as bad as TMax. Delta is somewhere in between, but I rarely use it anyway. Sheet Acros is now discontinued; I still have one box in 4X5, and many old negs from the Quickload system of that, but now shoot it mainly in 120; and ALL 120 films are a ring headache. Scanning gear suppliers once sold an aerosol AN spray which was effective and bound well to the film base. It was also unhealthy and meant to be used below a fume hood (which I did). But at least it was a distinct improvement over the old corn starch puffer bottles (offset powder). The last thing I want in my enlarger is particles of that, potentially getting onto other things inside the enlarger, and inevitably attracting booklice too. Fluid gate carriers seem like a cure worse than the disease, and are unrealistic for tightly sandwiched punch and register multiple film applications.

[mpålsson]

I've attempted to reach out to several companies that offer custom ANR glass, including Scan Tech, Glass Dynamics, Surplus Optics, Knight Optical, and Kienzle. I would've tried Focal Point, but it appears they've ceased production some time ago. Unfortunately, I haven't heard back yet from anyone. By any chance, can anyone recommend another source for high-quality custom ANR glass?

[Michael R]

I've attempted to reach out to several companies that offer custom ANR glass, including Scan Tech, Glass Dynamics, Surplus Optics, Knight Optical, and Kienzle. I would've tried Focal Point, but it appears they've ceased production some time ago. Unfortunately, I haven't heard back yet from anyone. By any chance, can anyone recommend another source for high-quality custom ANR glass?

I’m surprised you haven’t heard back from any of them. Keep trying. You can try Negative Supply. They have a similar product to Scan-Tech and are usually very responsive when contacted. The only thing is, in contrast to Scan-Tech they won’t have off-the-shelf pre-sized pieces for enlargers. You can try asking them if they can get something for you.

https://www.negative.supply/shop-all...x5-film-holder

You might also try contacting Heiland if Kienzle doesn’t respond. Heiland now sells unsharp masking systems and subcontracts to Maxim Bedov who makes the contact frames and registration carriers. These might use anti-Newton ring glass. Worth asking. https://heilandelectronic.de/film_punch

Alternatively try contacting Lynn Radeka, who I think still makes masking systems and carriers that can be ordered with ANR glass. I don’t know what type of ANR glass he is currently using but he might be able to help you, and cut some for you.

[mpålsson]

I’m surprised you haven’t heard back from any of them. Keep trying. You can try Negative Supply. They have a similar product to Scan-Tech and are usually very responsive when contacted. The only thing is, in contrast to Scan-Tech they won’t have off-the-shelf pre-sized pieces for enlargers. You can try asking them if they can get something for you.

https://www.negative.supply/shop-all...x5-film-holder

You might also try contacting Heiland if Kienzle doesn’t respond. Heiland now sells unsharp masking systems and subcontracts to Maxim Bedov who makes the contact frames and registration carriers. These might use anti-Newton ring glass. Worth asking. https://heilandelectronic.de/film_punch

Alternatively try contacting Lynn Radeka, who I think still makes masking systems and carriers that can be ordered with ANR glass. I don’t know what type of ANR glass he is currently using but he might be able to help you, and cut some for you.

Thank you! I'll try getting in touch with all of them!