Top glass in negative carrier advantages vs disadvantages.

[GoodOldNorm]

How many of you use glass in your negative carrier?
Glass in the bottom only, glass in the top only or glass top and bottom? Or if you use no glass do you use a cold light head or keep exposures short? How long does it take for a 4x5 negative to start distorting from the heat in a dichrioc or condensor enlarger, your thoughts please.

[Tin Can]

4X5 I use Neg-A-Flat

I have variations on stretchers for 5X7 and 8X10

[koraks]

No glass here. Too much hassle with dust, and I find it unnecessary for the size I print at. I.e., I cannot tell the difference between glass and no glass for the prints I make in terms of sharpness. I use a 'cold' LED light source + a stack of condensor glass so no heating whatsoever of the negative. Negative carriers are cobbled together from MDF, leftover bits of steel plate and magnets, and work surprisingly well, especially for 35mm & 4x5". Enlarger is a very ancient Durst 138 I got for free a few years ago.

The whole setup is an absolute joy to use for color and B&W from 35mm up to 4x5" (and maybe 5x7" but I don't shoot that size). I don't regret having shelved the various bits and pieces of AN glass I accumulated over the years and settling on a glassless workflow despite what some people say about it being 'impossible' to get good prints this way. If I can't see the difference even with a loupe, I'm good.

[bob carnie]

I use regular glass on bottom and AN glass on top, I stopped printing without glass carriers years ago. Keep the humidity up and have a negative setup station with the tools you need to clean neg. I do a lot of split contrast printing with lots of exposures and dread the negative popping .

[Tin Can]

Just to state the obvious

Glass negatives emulsion down and need nothing

[Oren Grad]

For 4x5 negatives, I use a carrier with top AN glass and bottom regular glass.


How long does it take for a 4x5 negative to start distorting from the heat in a dichrioc or condensor enlarger, your thoughts please.

It could easily be just a few seconds, but it depends on the design of your enlarger head, on environmental conditions in your darkroom and on your working habits. It could vary between printing sessions, depending on how tightly you control temperature and humidity in your darkroom, and it could vary within a printing session depending on how much time your enlarger lamp stays on for focusing and for exposures. Only way to know for sure is to carefully observe negative behavior in your own system with a grain focuser.

[neil poulsen]

Glass is a hassle, so I've avoided it. Plus, I've heard stories of having to deal with Newton rings.

I have an adapter where I can use Omega D5 carriers with my enlarger, and I have a Omega glass carrier. Were I to give this a try, I would use the bottom, but not the top glass. Maybe not as good as top and bottom glass, but limited hassle. Better than a regular, glassless negative carrier.

[Bob Salomon]

No glass here. Too much hassle with dust, and I find it unnecessary for the size I print at. I.e., I cannot tell the difference between glass and no glass for the prints I make in terms of sharpness. I use a 'cold' LED light source + a stack of condensor glass so no heating whatsoever of the negative. Negative carriers are cobbled together from MDF, leftover bits of steel plate and magnets, and work surprisingly well, especially for 35mm & 4x5". Enlarger is a very ancient Durst 138 I got for free a few years ago.

The whole setup is an absolute joy to use for color and B&W from 35mm up to 4x5" (and maybe 5x7" but I don't shoot that size). I don't regret having shelved the various bits and pieces of AN glass I accumulated over the years and settling on a glassless workflow despite what some people say about it being 'impossible' to get good prints this way. If I can't see the difference even with a loupe, I'm good.
Why if you have a problem with dust with glass does your dust not bother you without glass? Glass doesn’t make dust appear or disappear. And, if you have dust it will be further from the image plane with glass.

[Conrad . Marvin]

Keep it clean and you will not have dust issues. I use both glass with AN glass and non glass carriers with success. What I cannot seem to duplicate is my old enlarger had a glass carrier with a 1/4” plate glass top, but there were some marks on it which showed up on the print so I replaced it and got Newton rings. Finally I got a piece of AN glass and that quieted them down.

[Erik Larsen]

I use regular non an glass on both top and bottom for my Fotar with 8x10 negs. Have never seen any Newton rings. I think living in an area with low humidity helps my situation. For 4x5 with my Omega D5xl I usually go glasses.

[Drew Wiley]

I always use Anti Newton glass on both sides of the negative, all enlargers, all formats. Been doing it this way for decades, and it's impossible to get a truly sharp print otherwise, especially a big one. Other factors for me: 1) Unlike Erik at low-humidity Grand Junction, this is a foggy marine climate where Newton ring issues can be hell if not factored in; 2) I often incorporate pin-registered masks, which must be kept tightly sandwiched. Done right, no Anti-Newton texture will be visible. And having cut my teeth on big Cibachromes, I know what real sharpness in a print looks like, and what it doesn't; and there is no sharpness loss using high-quality AN glass below the image.

[Eric Woodbury]

I used glassless carriers for many decades, but when I switched to my own enlarger head and light source design, I went to 'glass' carriers as they are easy to make for all sizes of negatives. The top 'glass' is actually diffusion plexiglass. Doesn't matter which kind, but this eliminates Newton's rings. I've settled on using Satin Ice diffusion material. It has a slight texture and very little attenuation. The times when I do use an old glassless carrier, I put a piece of diffusion material within a half inch of the negative to eliminate the rings. And it does a good job of subduing dust, et al.

Truly diffuse light cannot form Newton's rings in such an arrangement. A diffuse light source such as coldlight or a diffusion head gives diffuse light at the source, but as the distance grows from the source to the negative, the diffusion is less.

For many years I used regular glass for the bottom piece. Cheap and plentiful, it worked fine. However, I recently reread Q.E.D. and the part about the 3% reflection in glass bothered me. At the local frame shop, I purchased some Tru Vue coated museum glass. It is coated on one side. The shop had some scraps that were big enough for my needs, so I got them for a song.

With this glass (coating side up against the emulsion side of negative) versus my float glass, I printed several step wedges on two occasions to see if there was a difference. Sure enough, there is. There was one more value of separation in the whites at medium contrast setting.

As for negative heating, there is little IR in coldlights, LEDs, or tubes. IR is abundant in hot lights such as tungsten and quartz. All light will heat whatever absorbs it, but there isn't that much energy transferred to the negative during an exposure, so removing IR from 'cold light sources' is unnecessary. With hot lights, the IR can be used for advantage. In one negative carrier long ago, the designer had a clamp to hold the negative in place in a glassless system. The negative could sag a bit, but when it heated just a little in the enlarger, the carrier expanded faster than the negative, thus stretching the negative.

[Tin Can]

Very logical!

[Drew Wiley]

Eric - I've tried at least two dozen kinds of AN material. At one time I had samples of 13 different kinds of official AN glass on hand. Now there might be only two or three manufacturers left. Textured plastic is not as reliable. In fact, none of it is truly dimensionally stable except frosted mylar, which actually contains a kind of pattern which can become annoyingly apparent in something like an open sky given enhanced contrast printing. And in this climate, optically coated smooth glass is useless when it comes to ring issues. I've experimented with all kinds of that too.

So-called Museum glass can be quite brittle, and one must be attentive to the chemical makeup of cleaners. There are different optical coatings involved, and some (the clear titanium coated type) can be harmed by ammonia. When cutting coated glass on my machine, I have to switch to a scribing roller made for tempered glass, which has a sharper bevel edge than what is customarily used for ordinary float glass. The edges have to be relieved more carefully too. Technically, museum glass has an slight amber or pinkish anti-UV tint; whereas the un-tinted versions are simply referred to as optically coating anti-reflective glass, though under various brand names per se.

And now there are optically coated acrylic sheet materials too - very pricey unless you find scraps of those. Since the coating is applied to baked-out sheeting, it will be more dimensionally stable than ordinary acrylic sheet relative to progressive hydration, but will likely still slightly bow toward a heat source, that is, end up slightly convex in relation to any negative below. This is apt to be a far bigger problem with 8X10 work than 4x5 due to the larger surface area involved, though I have successfully used 8X10 cold light setups with a piece of acrylic above / glass below.

[koraks]

Why if you have a problem with dust with glass does your dust not bother you without glass? Glass doesn’t make dust appear or disappear. And, if you have dust it will be further from the image plane with glass.

2 additional surfaces that dust & dirt can adhere to per piece of glass, so 4 additional surfaces if bottom and top glass is used. But you know this perfectly well. So let's hear the real reason you're asking this - what do you think I should be doing differently? Might as well say it directly.

[Bob Salomon]

2 additional surfaces that dust & dirt can adhere to per piece of glass, so 4 additional surfaces if bottom and top glass is used. But you know this perfectly well. So let's hear the real reason you're asking this - what do you think I should be doing differently? Might as well say it directly.

All enlarging lenses are developed and manufactured fora perfectly flat negative that can not pop and used on a properly aligned enlarger. They also,perform optimally only when used at optimum aperature and within their optimal magnification range.
The first step to quality prints is alignment. The second is a glass carrier..

4 more surfaces to clean is an excuse keeping you from printing at your best.

[koraks]

So what if I manage to keep my negatives perfectly flat and aligned without using glass and without any risk of them popping? I get the benefits you speak of and the benefit of less risk of dust.

FYI, dust has always had far more impact on the quality of my prints than alignment and flatness issues. Not to mention Newton rings, which are a fact of life with films such as TMX in a climate that is often fairly humid.

I'm not saying a glassless approach is fundamentally better than one without glass. I am, however, advocating a real-world approach that takes into account local conditions, enlarger architecture and personal abilities/preferences. I don't see the need to dogmatically stick to one proven way only if other options work just as well in practice, or even better for some of us.

[LabRat]

Additionally, using a heat absorption glass near a hot light source is helpful, as it cuts a lot of the IR that causes the film to buckle/pop in any carrier... It will reduce Newton rings in glass carriers, as film has a more even tension under glasses, and in glassless carriers, film is not heating/drying and "popping" like before...

Steve K

[AJ Edmondson]

Glass (AN) top and bottom... been doing it that way for over fifty years. I do put in a little extra effort to eliminate dust but nothing particularly onerous and I don't see any reason to not avail myself of the quality resulting from a flat negative.
Joel

[Bob Salomon]

So what if I manage to keep my negatives perfectly flat and aligned without using glass and without any risk of them popping? I get the benefits you speak of and the benefit of less risk of dust.

FYI, dust has always had far more impact on the quality of my prints than alignment and flatness issues. Not to mention Newton rings, which are a fact of life with films such as TMX in a climate that is often fairly humid.

I'm not saying a glassless approach is fundamentally better than one without glass. I am, however, advocating a real-world approach that takes into account local conditions, enlarger architecture and personal abilities/preferences. I don't see the need to dogmatically stick to one proven way only if other options work just as well in practice, or even better for some of us.

You can’t keep them flat without popping without glass.

[Tin Can]

Many enlarger makers made glassless film carriers

Glennview has his own design

Tim Layton uses Calumet (https://timlaytonwildhorses.com/)

I have 2 Calumet, bought from members here, when they went Digi

Very simple and very delicate in usage, just setting the frame and neg down too quickly on a flat surface can disturb

But once you know how

perfect

don't buy a bent one, Impossible to FIX

[Tin Can]

Here is Tim using one

https://www.timlaytonfineart.com/HeilandLED

[Michael R]

I think (like most things in the darkroom) if your negatives are staying flat/you are not losing any visible amount of print sharpness, you might as well continue as-is.

I’ll say a few things:

1. I think Bob is right regarding the dust argument against glass carriers. This is a non-issue. In fact glass might be better.

However…

2. Newton rings can sometimes be a difficult problem to solve. A tip I came up with a long time ago which might help people in a pinch, at least on the top surface of the negative) is to use a piece of unexposed, fixed out TXP (Tri-X 320) between the top glass and the negative. Because the base of TXP is designed for retouching, it has just enough “tooth” (texture) to usually prevent the formation of the interference pattern. So basically both the base and emulsion sides of the film should suppress Newton ring formation, and you don’t need to worry about whether or not the texture of ANR glass, Mylar etc. is fine enough. If you get Newton rings below the negative (sometimes can happen with films that have a shiny emulsion surface such as TMax and Acros) it’s a less trivial problem to solve.


So what if I manage to keep my negatives perfectly flat and aligned without using glass and without any risk of them popping? I get the benefits you speak of and the benefit of less risk of dust.

FYI, dust has always had far more impact on the quality of my prints than alignment and flatness issues. Not to mention Newton rings, which are a fact of life with films such as TMX in a climate that is often fairly humid.

I'm not saying a glassless approach is fundamentally better than one without glass. I am, however, advocating a real-world approach that takes into account local conditions, enlarger architecture and personal abilities/preferences. I don't see the need to dogmatically stick to one proven way only if other options work just as well in practice, or even better for some of us.

[Tin Can]

I am not arguing against glass

I am using an alternative

Same with lamps

DIY is LF

[Bernice Loui]

Glass and glass-less film carriers have their place depending what the print goals-needs are.

Glassless film carriers are easier to manage dust and general set up, but they can never keep the film flat as a proper glass film carrier. Glass film carriers have the ability to keep the film flat and stable over the time needed to make a GOOD print.

That said, roll film (35mm & 120) in the Durst 138 tends to bias towards glassless film carriers as the print quality is traded off for the number of prints that need to be made -vs- print quality. The glass carrier in the Durst 138 allows placing roll film sections making an enlarged contact print. Essentially, glassless film carriers trades off speed of set up for film stability in the enlarger.

If a serious print is made from 5x7 B&W film, it will go into the glass carrier. The Durst 138 film carrier has anti-newton glass on top with clear magnesium fluorite reflection aiding glass on the bottom (Durst item). Once set up, the film in the Durst film carrier will remain absolutely stable for hour after hour of printing. This does NOT happen with a glassless film carrier. The film in glass carrier will be held.. flat and stay flat. This will go a long ways to producing a nice sharp print given the enlarger is properly set up. Never had any issues with Newton rings using Durst anti-newton ring glass on top, Durst clear AR glass on the bottom. And no, stopping down the enlarging lens alone does not compensate for poor enlarger set-up/alignment and a enlarger that cannot remain stable and in alignment over the entire travel of the enlarger head to base board distance.

There is an unwavering preference to using the Durst 138 condenser head for all B&W prints as this condenser head properly set up with APO process lenses will produce sharp, snappy images diffusion enlargers cannot. This preference for the Durst 138 condenser head came after making piles of prints using both the Durst diffusion insert and other diffusion light sources in the Durst 138, then back to a properly set up Durst 138 condenser head.

This brings up the topic of both dust issues with glass -vs- glassless film carriers and the effects of differing light sources used in the enlarger.

As for dust, much like camera film holders, keep them and the working environment clean (Darkroom air filtration helps) goes a remarkable long ways to greatly reducing this problem.


Bernice

[Bernice Loui]

Durst 138 condenser head has a very effective IR suppressing system. It has a IR suppression glass filter, plus forced air cooling, plus a mirror to send the light path 90 degrees on to the condenser set which further suppresses IR/heat finally reaching the film carrier.

There is a filter slot in this light path allowing placing paper contrast filters in the light path instead of in front of the lens where these paper contrast filters can impact print image quality.



Bernice



Additionally, using a heat absorption glass near a hot light source is helpful, as it cuts a lot of the IR that causes the film to buckle/pop in any carrier... It will reduce Newton rings in glass carriers, as film has a more even tension under glasses, and in glassless carriers, film is not heating/drying and "popping" like before...

Steve K

[Drew Wiley]

Koraks - just depends on how demanding you are in terms of print sharpness. I have a friend who manages rather well with a glassless carrier for 6X6cm negs; but I can't personally imagine doing that for even 35mm film. Tried that long ago, and learned the hard. The larger film gets, the harder it is to keep flat. And the larger prints get, the more obvious the issue will be. Yes, the cooler the light source, the less the risk will be. But for someone like me, who needs very predictable precise results, often involving integrated pin-registered supplemental sheets of film, glassless would be anathema.

The idea that going glassless makes life easier with respect to dust - again, all depends. That won't protect you from little bits of dust settling on the film directly during exposure. If it's going to happen, I'd rather spend the extra work to meticulously clean the glass first, focus tightly on the emulsion grain, and have a bit of distance between that and any dust. And having cut my teeth of big Cibachromes, which could be a nightmare to retouch, I learned how to work very clean to begin with.

Scientifically, there is a correct answer to flatness and consistent precise focus, and it is glass on both sides. But in practical terms, everyone is obviously free to do what works best for them personally.

[Tin Can]

I will add, I process most film in Kodak Film Hangers with gentle gas burst partly to keep film flat

My film is very flat as it is hard to get rid of the slight air cushion when I do a dry flat on scanner glass scan

Stuffing film in cylinders, then wetting film with chems for a while does make a curved 'set' to film

[koraks]

Scientifically, there is a correct answer to flatness and consistent precise focus, and it is glass on both sides.
Scientifically, the best approach would be a glassless system that ensures perfect flatness and alignment in a dust-controlled environment (cleanroom). Glass in carriers is a compromise to ensure flatness and alignment. In practice, the compromise is evidently entirely satisfactory IF the glass is kept meticulously clean at all times. Personally I have always admired the tension system on the Durst Laborator negative carriers - a brilliant solution. I think Beseler had something similar, but with the unacceptable drawback that it very easily damaged the film.

[LabRat]

Another downside I have encountered while printing with glass carriers was when I was printing vintage sheet film negs (for a book project), and negs came from the (soggy) NE... Took a neg out of sleeve and examined on the light box first... Noticed it slightly started to warp, so left it out for awhile... Placed in glass carrier with condenser enlarger and examined it on easel, but noticed Newton rings were changing while I watched... Left light on for some time, and took out neg + carrier and reflected light off of it, but noticed reflected highlight had a very slight ripple in it... Put back into enlarger to "cook" it some more, and noticed a ring appearing around edges of neg...

I figure the neg had a high moisture content, and even with slight heating from light source started to cause uneven drying on neg with a almost imperceptible wave even between glass, and edges were drying differently as moisture could leave from there, but not as much from center of neg... Film would touch glass differently while sandwiched, and came out warped... Had to hang the rest of the negs from the job in the drying cabinet for a day unheated to slowly dry the films...

Had also had to print roll negs during very dry conditions (2% RH, where my fingers were like 10 spark plugs when I touched anything) and had Newton issues I never had before, and film warping and roll strips were rolling up like drinking straws (rehydrating it in moist environment solved issue quickly), but glass carriers in those extreme conditions were asking for trouble, and pull out glassless on those soggy or very dry nights...

Steve K

[Bernice Loui]

Tooted Lots about the goodness of a proper Durst enlarger, some do not appreciate what some of these Good Durst enlargers offer in real world print making.. Then sticking to their table top enlargers (the iffy ones) with lots of complaints and tolerating it.


Bernice




Personally I have always admired the tension system on the Durst Laborator negative carriers - a brilliant solution. I think Beseler had something similar, but with the unacceptable drawback that it very easily damaged the film.

[Drew Wiley]

I just now noticed Michael's previous post. Sorry about that, Michael. Yeah, I sure miss the retouching tooth which accompanied classic sheet films of yesteryear. Nowadays many sheet film products are annoyingly smooth with respect to ring issues. The scanning texture built into current Kodak color sheet films like Ektar and Portra is somewhat helpful. A week ago I reprinted an old sheet which still had the Anti-Newton spray I applied to it. That seems to have been discontinued for safety reasons (I always used it under the fume hood anyway); and now most scanning is done via mounting fluid instead. The old press room recipe of finely sifted corn starch sounds like a horror story inside an enlarger bellows, potentially attracting booklice. But I'm not going to move to the desert to avoid ring issues; the low humidity there and clay dust could be an even bigger headache.

I take my time to clean all the necessary carrier glass in advance of each session, then load up the various glass carriers used with respective enlargers, and set them aside in clean drawers, so that things will go faster on the printing day. It's just a mantra by now. I can be a little more casual with basic black and white printing, since minor issues are relatively easy to spot or retouch. But when doing serious color work, I sponge down the entire cleanroom and strictly work in a true 100% dacron cleanroom smock. Sometimes multiple sheets of film have to be generated by contact completely dust and ring free. So my pin-registered contact mask itself is equipped with Anti-Newton glass, a thick type no longer available, unfortunately. I have all kinds of special related gear, some made by Condit, some by myself.

Koraks - your position might be fine for your own purposes, but would be a non-starter for anyone with a background in serious graphics arts, the printing industry, or advanced color darkroom printing. It is IMPOSSIBLE to keep film consistently flat just floated or stretched into position. That's why everyone on this forum, or anywhere else for that matter, with a distinct background in anything I have just mentioned, comes to the same conclusion as me. It's either glass, or failure, with respect to the necessary degree of precision. I started out color printing, with masks integrally involved, so fell into the routine automatically. There was no other choice. Everything would be out of register if I didn't use precise glass carriers. All of Durst's top end carriers were not only designed for glass, but were pin registered too. I should know. I have a two machinist cabinets full of commercial Durst accessories, plus some of my own related devices. But if Durst THEMSELVES ever made a tension carrier, please quote the model number.

Everything I'm aware of in that respect was AFTERMARKET, not their own. Yes, I could be wrong. I only work with their true commercial series equipment (L138, L184, etc), and am unfamiliar with the amateur line of equipment. And they dabbled in all kinds of options over the decades. Sizing masks for glassless were certainly made, and tensioning options for continuous rolls, for sake of printing by frame sequences. I know someone who still has one of those highly automated roll film Durst enlargers. Still, I'm skeptical until proven wrong with respect to sheet film stretchers per se. Are you sure it wasn't somebody else who made them? I don't want this to be the heart of the debate, but am simply curious who first came up with the idea. Durst did at times market things outsourced to others to actually make, like cooling fans for example.

[Bernice Loui]

Hard lessons learned about Durst enlargers and glass film carriers happened during the later 1980's with the first Durst 138. Once that Durst 138 and related darkroom was set up, print making began. Prep work for sheet film in the Durst glass carrier was not simple and tedious to keep everything clean as possible. Once the film was clean, carrier clean, film loaded into the carrier then into the 138, all was great. Absolute stability of the film projected image to the base board for hours or as long as one wants to work on that sheet of film.

The tedium and hassle of setting up sheet film in the Glass carriers promoted to try glasses sheet film carriers.. They were some what easier to set up initially, but the film stability over the hours needed to make a decent print was hit with much print waste due to the film shifting in the glassless film carrier. Back to the glass film carrier and investing the time needed to keep everything clean as possible to negate any retouching/spotting of the print.

Kinda of a pay later or pay now deal with glassless -vs- proper glass film carriers.


Bernice




It is IMPOSSIBLE to keep film consistently flat just floated or stretched into position. That's why everyone on this forum, or anywhere else for that matter, with a distinct background in anything I have just mentioned, comes to the same conclusion as me. It's either glass, or failure, with respect to the necessary degree of precision.

[koraks]

> Are you sure it wasn't somebody else who made them?
Yes. Durst L1200. Of course, I wouldn't know because I use the old-fashioned amateur 138 and don't have a background in the graphics arts industry, so whatever I experience or think is invalid. Happy printing, Drew.

[Tin Can]

At least here in Middle Kingdom USA it seems Elwood enlargers were/are the most made/available to mere humans

They still pop up, Durst not so much

But the good news is they do use glass film carriers! Happy Day!

However that Art Deco Swan neck is a bit to align, I keep 3 as sculpture!

I loved Elwood on first glance


Maybe LFPF is NOW all experts, who use only the finest gear and process, but I doubt it


Carry ON!

I WILL interrupt as I see fit...:cool:





but this old hobbyist is satisfied with my process and Art

[Drew Wiley]

You have it all upside-down, Koraks. L1200 is a fine product for sure, but came out of the amateur division. It's made of things like aluminum extrusion. The L138's and 184's etc were true commercial enlargers with many machined solid components, designed for long-term commercial reliability and optimal precision to begin with. These came out of an entirely different division. It would be almost impossible to make things that way again due to labor costs. True Italian machining during it's peak era. A single matched carrier setup for one of these might have cost more originally than an entire L1200 with colorhead. But you still haven't provided me with an actual Durst part number for the alleged tension carrier.

But it's all just a fun academic debate at this point. Take it in stride. All that matters is that you are happy with your equipment, just like I am with mine! I just happen to also enjoy refurbishing fine older enlargers, or building new ones - the inevitable shop project itch. I leave it to neighbors to fix up old classic cars instead, or speedboats, or motorcycles (or sometimes burn down their own shop trying! - it did happen).

[Drew Wiley]

Elwood? Doesn't every hair salon use those to dry old lady beehive hairdoos? Or am I thinking of Beseler beehive units? Where does Marge Simpson get her blue hair done? - they would know.

[Tin Can]

Jake


Elwood? Doesn't every hair salon use those to dry old lady beehive hairdoos? Or am I thinking of Beseler beehive units? Where does Marge Simpson get her blue hair done? - they would know.

[Michael R]

Not if you use high quality film. Stuffing film in cylinders is also best as far as uniformity goes. Pick your poison.


I will add, I process most film in Kodak Film Hangers with gentle gas burst partly to keep film flat

My film is very flat as it is hard to get rid of the slight air cushion when I do a dry flat on scanner glass scan

Stuffing film in cylinders, then wetting film with chems for a while does make a curved 'set' to film

[Drew Wiley]

Hmmm .... snooping around for "glassless" neg carriers for Durst, I did get quite a few hits of sandwich-style carriers like the Nega 138, simply missing their original glass, which you'd still have to come up with yourself. And there are people like Glenn Evan who will custom make a glassless carrier for you, potentially starting with an old official Durst carrier. No actual Durst numbers so far. It would be nice if Durst had at least put out a numerical index listing all the options, whether currently in mfg or not, like the Sinar Code did for their own endless accessory business. But again, all academic and fun what-if related. I already have what I need.

Of course, the ultimate option for eliminating rings during enlargement would be a fluid carrier. But that would amount to a lot of mess and hassle, and a lot worse than the disease it cures if negs need to be stacked in register. So pick your favorite poison.

[Tin Can]

I use all brands of film

Even Kodak

We are constantly told by all you experts here

Test for yourself

I do and I make my own decisions

I worked most of my life in test labs

Used miles of Fujifilm Pressure sensitive film (https://www.fujifilm.com/products/prescale/prescalefilm/)

and shot lots of Polaroid evidence

Used huge tanks of liquid N2 and 5K tanks

We were doing actual fresh science




Not if you use high quality film. Stuffing film in cylinders is also best as far as uniformity goes. Pick your poison.

[Drew Wiley]

Film is easy to flatten. Same device that works well for road kill. Of course, you'll need to remove the tread marks afterwards.

A couple of hours ago I came back from the outfit that does my C41 processing, with a roll of 120 film all curled up inside a little box. I just hung it from my sink room clothesline, and weighted it on the end with another clothespin. It will be plenty straight tomorrow. But going back through a long forgotten stack of 8x10 chromes and finding a promising image with a bent corner due to being scrunched in a drawer is a different challenge. I'll keep it under a flat weight for the remainder of the year. I'm not color printing at the moment anyway.

[ic-racer]

From what I can tell from internet search and brochures, the last generation of Durst 10x10 enlargers only had glass carriers. This would be the L1840 and the HF Horizontal series. When I got my L1840, knowing Durst expected me to use glass all the time (a fan blows on the negative carrier during exposure), I converted all my other enlargers to glass/glass.

[Drew Wiley]

Well, I don't see any clue that Glenn Evans actually sold any of his jerry-rigged ones, nor does he give a model number for the hypothetical 184 glassless version by Durst itself. But in his description of that, it does resemble an old Durst carrier in my bone pile of horse-traded odds and ends. What is ironic, however, is how the lab where it came from had converted that itself to fully glass, both sides.
It would have been useless to them otherwise, knowing the relatively huge size of Ciba prints they did, and the long intense exposures involved.

[Tin Can]

Ciba prints!

Extinct

I was wondering how/why some were running hot lamp for hours on a single neg

Not applicable to most these days

https://en.wikipedia.org/wiki/Ilfochrome#History

[Drew Wiley]

Those "hot" high powered enlargers were printing Cibas in about 15 or 30 seconds, even with relatively dense contrast masks attached. Not hours. A transparency left in those conditions even two minutes might be faded to worthlessness. My own color mural enlarger had to be cooled with four separate pure silicone hoses. Just the cooling fan used more energy than a typical big industrial table saw. That's why I got rid of the thing and built my own custom 8X10 colorhead to be far more efficient, energy and cooling wise. The downside is that that my own colorhead is rather massive and heavy, and requires a pulley system just to lift off. Now that the Ciba era is over, the name of the game is how to prolong exposures so they won't be too fast using RA4 chromogenic paper instead. But I worked all that out over a decade ago.

Very long exposures were counterproductive. Not only did reciprocity failure start kicking in with Ciba anything more than a minute, or severely after 2 min, but prolonged excessive heating of dichroic filters alters their spectral transmission. I do know someone who built his own colorhead using a rheostatic system much like that well-known AA antique, using a bank of many individual tungsten bulbs, but in this case, composed of a mix of RGB filtered multiple ones. Rheostats of course cut power, and he ended up with exposures of 8 or 9 minutes. Another flaw is that he used ordinary pegboard for his vacuum easel, so if one looked carefully, regular little 1/8 dots of slightly greater density sometimes became visible in his prints.

My own rig is full feedback circuitry pulsed RGB halogen, 8X10 capable, with short printing times. But it is somewhat schizophrenic if any EMI incident occurs. There is no way to fully avoid that unless computerized sine-wave lighting controls are employed, like are now used for very complex stage lighting or rock concert productions. But that option wasn't available yet, and I wouldn't want to have been dependent on rapidly obsolete software or hardware anyway. As a backup option, I have an ordinary Durst L184 fitted with their own 10x10 CMY subtractive head.

[bob carnie]

Those "hot" high powered enlargers were printing Cibas in about 15 or 30 seconds, even with relatively dense contrast masks attached. Not hours. A transparency left in those conditions even two minutes might be faded to worthlessness. My own color mural enlarger had to be cooled with four separate pure silicone hoses. Just the cooling fan used more energy than a typical big industrial table saw. That's why I got rid of the thing and built my own custom 8X10 colorhead to be far more efficient, energy and cooling wise. The downside is that that my own colorhead is rather massive and heavy, and requires a pulley system just to lift off. Now that the Ciba era is over, the name of the game is how to prolong exposures so they won't be too fast using RA4 chromogenic paper instead. But I worked all that out over a decade ago.

Very long exposures were counterproductive. Not only did reciprocity failure start kicking in with Ciba anything more than a minute, or severely after 2 min, but prolonged excessive heating of dichroic filters alters their spectral transmission. I do know someone who built his own colorhead using a rheostatic system much like that well-known AA antique, using a bank of many individual tungsten bulbs, but in this case, composed of a mix of RGB filtered multiple ones. Rheostats of course cut power, and he ended up with exposures of 8 or 9 minutes. Another flaw is that he used ordinary pegboard for his vacuum easel, so if one looked carefully, regular little 1/8 dots of slightly greater density sometimes became visible in his prints.

My own rig is full feedback circuitry pulsed RGB halogen, 8X10 capable, with short printing times. But it is somewhat schizophrenic if any EMI incident occurs. There is no way to fully avoid that unless computerized sine-wave lighting controls are employed, like are now used for very complex stage lighting or rock concert productions. But that option wasn't available yet, and I wouldn't want to have been dependent on rapidly obsolete software or hardware anyway. As a backup option, I have an ordinary Durst L184 fitted with their own 10x10 CMY subtractive head.

Well not to be an ass , but I have to disagree with this Drew. In 1988 era the Dome Stadium was built in Toronto which still hosts the Toronto Blue Jays. Scarborough Colour Labs was the only photo lab allowed to put any signage in the Stadium, around the Stadium and of course all the concourses and walkways leading to the Dome. We are talking a monster job. The first round of work was all backlight Ciba Clear and front lit Ciba pearl prints. I was hired at the beginning of production and for 9 months worked every day on every aspect from taking in work, photo comp, print production and mounting and framing into custom light boxes.

The print material on normal size mural cibas was normal enlarger times, but we also did multiple montage huge images which consisted of 4 ft x 10 ft panels that were then stripped together in the finishing department. My good friend was Jack Seary who in my estimation was one of the worlds greatest photo comp negative technicians at the time. We were using horizontal Durst enlargers and Jack would produce the 8 x 10 dupe composite , and one or two logo colour hits and a white hit negative . We had about 10 mural rooms and two were designed for this huge complicated work. A single Ciba Clear trans could take up to 4 hours to produce which involved a couple of exposures. The room itself was a room within a room where nobody could walk into as the technician would lock in and none of the walls were connected to any corridors for wall shake.

Everyone knew when the two rooms were working and nobody would dare go near them, these rooms were operating double shifts 7 days a week for over a year.

[bob carnie]

Oh one thing, the darkrooms were all painted black , the technician wore black and glass carriers were mandatory.

[koraks]

Well, I don't see any clue that Glenn Evans actually sold any of his jerry-rigged ones, nor does he give a model number for the hypothetical 184 glassless version by Durst itself.
It was apparently one of the options to use with the Laraneg carrier system. See here, particularly Gary Mulder's post: https://www.largeformatphotography.info/forum/archive/index.php/t-70332.html
He probably knows, as he has one. Which I know, because I've seen it in his darkroom. To avoid any confusion: Glenn Evans likely has nothing to do with the glassless Durst holder I've seen on Gary's enlarger.

[Drew Wiley]

Bob - I don't understand what you are "disagreeing" about. What you state doesn't conflict with anything I said. Ciba was a dominant color process during at least two decades, and different labs and individuals had all kinds of options in terms of colorheads and so forth, as well as the complexity of jobs they could handle. The whole problem with the big Durst heads as well as the smaller Starlight is that they ran so hot that the dichroic filters got eaten alive, and sometimes had to be replaced nearly every six months at considerable expense. The early Durst mural head also had parabolic dichroic mirrors which were equally expensive to replace or recoat.

Note that I was referring to printing times, which did not involve hours, but at most a minute or two, and was not referring to how much background work potentially went behind it, before the actual printing. I've used up to 13 sheets of 8X10 film myself in terms of pre-masks and so forth just to arrive at a one master printing dupe, though just two was more typical.

There was at least one very huge Ciba operation here too, in terms of actual facility size and the sheer scale of the processing equipment. But every big lab had some kind of mural option. Not all wanted to deal with the plumbing issues, nasty fumes, extra permits, special processors, and sheer facility maintenance expense of high-volume Ciba output. I had none of those issues because I was just doing low-volume personal work in drums, and not any bigger than 30X40 inch prints. But in my day job I did interact on a regular basis with the owners of most of those labs in terms of their facility needs. They became good friends.

[Tin Can]

Read down and what about wet oil mount negs which are also discussed here

http://www.glennview.com/durst.htm

[Drew Wiley]

Yeah, old odds n ends of Carlwen are still around. But nowadays it would be easy to CNC something aluminum better if one wanted to go down that messy route. Phenolic certainly isn't ideally dimensionally stable; I've worked with a lot of that myself. The advantage of working dry is that you can simply tape the final mask to the original piece of film when on the register pins, remove the intact sandwich, and place it inside the carrier (unless doing sequential tricolor printing). Those little registration holes only last so long until they potentially get distorted, so the tape method reduces cumulative negative torture. And going the fluid route when stacking films means a lot more surfaces need to be treated, kept bubble free, and then subsequently fully cleaned separately from each other.

Fluid mounting might make more sense with just a single piece of film when point light source condenser heads are being used, which are especially unforgiving of dust and scratches. And fluid gates for film scanners involve only a single piece of film in position at a time.