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panchro-press
21-Nov-2010, 07:25
I've been reading with interest about the emerging films from Middle and Eastern Europe.

Does anybody know if any of these films are a match for the thick emulsion, characteristic curve of Kodak Super XX?

Dave

-30-

Ole Tjugen
21-Nov-2010, 07:27
No, they are not. All are "thin emulsion" films.

IanG
21-Nov-2010, 07:32
Fortepan 200 was the direct successor to Super XX which was made in the same factory from early 1939 in Hungary by Kodak Ltd (London). The German & Hungarian plants were controlled from the UK, but the Forte plant was nationalised after WWII by the communist regime.

So if you can find some Forte 200 it's essentially just a slightly more modern version.

Ian

Mark Sampson
21-Nov-2010, 07:50
Ten years or so ago Bergger BPF 200 was introduced in the USA; it was advertised as being similar to Super-XX. Gordon Hutchings, of PMK-Pyro fame, said that it was; other people disagreed. I tried some, a nice film, but I'd never shot Super-XX as a camera film, so can't comment. That film seems to be gone now as well, and in the tangled world of smaller b/w makers/marketers it's hard to tell who made that film or what other brand(s) it might have been sold as. Someone here will know...
I believe that the real reason Kodak kept Super-XX in production (in Rochester anyway), until 1990 or so was for dye-transfer printers. S-XX's color-response curves matched exactly, a requirement for making accurate color-separaton negatives, and no other film could do that. (I worked in a custom lab in the late '70s, where we made b/w internegatives from color transparencies on Super-XX; my only real experience with that film.)

Jay DeFehr
21-Nov-2010, 08:07
I still have a bunch of Fortepan 200 in my freezer. I don't know how similar it is to SXX. It's a nice film in its own right, but I would trade it for TMY-2 without hesitation.

IanG
21-Nov-2010, 09:21
Bergger BPF200 was re-badged Fortepan 200, and the Forte/Bergger 400 film was based on pre-WWII Tri-X.

No other manufacturer's films will be as close as the Forte films purely because that Forte plant continued making the pre WWII Kodak films under the Germans and then the Communists until the collapse of the Eastern Block.

Ian

Michael Kadillak
21-Nov-2010, 11:21
Ten years or so ago Bergger BPF 200 was introduced in the USA; it was advertised as being similar to Super-XX. Gordon Hutchings, of PMK-Pyro fame, said that it was; other people disagreed. I tried some, a nice film, but I'd never shot Super-XX as a camera film, so can't comment. That film seems to be gone now as well, and in the tangled world of smaller b/w makers/marketers it's hard to tell who made that film or what other brand(s) it might have been sold as. Someone here will know...
I believe that the real reason Kodak kept Super-XX in production (in Rochester anyway), until 1990 or so was for dye-transfer printers. S-XX's color-response curves matched exactly, a requirement for making accurate color-separaton negatives, and no other film could do that. (I worked in a custom lab in the late '70s, where we made b/w internegatives from color transparencies on Super-XX; my only real experience with that film.)

I read the same article in View Camera Magazine and immediately went out and purchased the film. When I plotted it up I quickly realized that selective utilization of the data was being employed in the write up that was not conveying the complete story. Yes, the film curve has a very linear straight line "middle" section (that under normal circumstances can be quick effective for conventional silver printers) until the curve takes a hard right and tends to flattens out. If you do not plot the WHOLE film curve does not mean that it is not there. If any author is going to make a quantitative comparison of any film it should be representative of the full Monty apples to apples particularly considering that alt process photographers and Azo printers that look for the linear "to the moon" density building character of Super XX. Seemed to me to be more sales hype and opinion journalism than scientific in nature but maybe that is just me. I have Super XX in my freezer and it does precisely that.

There is no question that the closest thing to Super XX in the complete spectrum of sheet film offerings is T Max 400, which just so happens to be sharper than its former Kodak counterpart.

Jim Noel
21-Nov-2010, 12:19
I agree with Michael. I have tested every "clone" when announced and compared it with some of the Super XX which I still have. Although some have had a relatively straight middle section, they either have too much toe, or too much shoulder. I have not found anything close.

Michael Kadillak
21-Nov-2010, 16:18
Michael has this one right. The straight line of TMax 400 really allows you leeway in shooting and development. A nice film.
Bergger sucked big time. You could develop it, see you needed expansion while developing and so develop it longer. No change, it just got to a point and did nothing more than start to fog. For pushing a bit and expansion development it was as responsive as wet flour tortillas.

Now if only Kodak would quit playing games with Tmax 400 availability, sizes and packaging it would be one I would gladly use. As it is, non-availability in some normal sizes and 10 sheeet boxes in 8x10 keep me shooting Ilford.

Up to this point in time I had considerable respect for Gordon Hutchings and accepted the conclusions of his article without hesitation. After the fact I was terribly disappointed that he wasted my time with such a misguided conclusion. Gordon will never be labeled as lacking in the cranial department when it comes to photography so it sure sounds like he was more interested in financially representing Bergger than writing a truthful article. It happens.

While I wish things were different with Kodak. That said I know for a fact that their film is available in 8x10 so I am getting ready for a 30 box order of 8x10 and have a dozen old 50 sheet boxes to personally package it in for my freezer. My conclusion is having access to the nest film available trumps the packaging inconvenience.

Drew Wiley
21-Nov-2010, 18:06
I'm starting to shoot my last box of 8x10 Bergger 200, which is my favorite film ever in this format. After that, it will be TMax400. Bergger 200 is a straight line film with very little toe, and in this respect just like Super XX but finer grained. The
spectral sensitivity is also very similar. Where it differs it that it doesn't push well
above N+1 or N+2, so in this respect might have disappointed contact printers using
it for very long-scale media. Another discontinued product, Fomapan 200 (aka Classic 200, Arista 200) had even less toe (virtually none) and could be developed
to higher contrast, but had a number of quality control issues and certainly wasn't
a true 200 speed film. The new TMax400 has a bit of toe, but much less than most
films, and relatively long straight line. It's ability to be pushed to high contrast has
so far evaded me, at least without distorting the straight line. No problem for a
projection printer like me, but contact printer have different issues. Bear in mind that I have tested these films not only for general black and white work but for very
criticial color separation use which demands a matching straight line in all three separations, which has been plotted with a densitometer.

Drew Wiley
21-Nov-2010, 18:19
Mark - I belive you are incorrect about why Super-XX was discontinued. After all,
it was the preferred black-and-white film of most photography schools for many years due to ease of use. But it was quite grainy, and as smaller formats gained popularity, was pushed off its pedestal by the newer T-grained emulsions. It was also a very proprietary thing requiring a tradition of highly skilled personnel and not just a formula. Nor did all three separations match well. The "blue bump" of the blue separation being unable to rise to the same contrast level as the red and green separations was infamous among dye transfer printers. Bergger 200 has the same problem. In fact, both 100TMax and 400TMax are far more cooperative in this respect, and in my opinion are actually better for color separations than Super-XX ever was, though there's a new learning curve involved with the developers. I don't
know about schools everywhere, of course, but here at UCB, 400TMax is the new
"standard" sheet film, with reliability and great versatility. (And yes, there are still
plenty of students interested in view cameras.)

sanking
21-Nov-2010, 19:00
I agree with Michael and Dakotah. Bergger 200 was a sub-par film that was market hyped as a substitute for Super-XX, when in fact it lacked the most important characteristic of Super-XX, i.e. the ability for expansion development. And yes, this lack of ability to be expanded is exactly why it appealed to many people who don't understand how to control contrast. With BPF 200 you got the same contrast, almost irrespective of how long you developed it.

I used Super-XX for many years before it was discontinued. With the possible exception of a fairly straight line curve BPF 200 was nothing like Super-XX, and this in spite of the BS marketing that told us that it was.

Sandy King

Michael Kadillak
21-Nov-2010, 19:32
Mark - I belive you are incorrect about why Super-XX was discontinued.

Super XX was discontinued primarily because of the fact that the associated chemistry to product it became environmentally impossible and costly to comply with recently enacted EPA regulations. It had a vibrant following in LF/ULF circles for which sales were very consistent. This came straight from the folks that know.

Gary L. Quay
22-Nov-2010, 02:31
I tried Bergger 200 specifically because of the comparisons to Super-XX. I was underwhelmed by its performance. I never used Super-XX because I took up photography seriously in the mid 1990s, after it had gone off the market, but I really wanted a film that would respond to Zone System controls. What I got was a waste of both money and time.

--Gary

IanG
22-Nov-2010, 05:17
The marketing hype of Fortepan/Bergger 200 was correct but people are comparing it to post WWII Kodak Super XX.

Most Kodak emulsions changed significantly over the years but the company never made a distinction by altering the product names. So while Super XX was in production for just over 50 years and Tri-X has been around for over70 years there's no distinguishing the generations and step changes.

In comparison Ilford over the same period (late 1930's onwards) renamed their films going from Fine Grain Panchromatic & Hypersensitive Panchromatic, through FP2/HP2, FP3/HP3, FP4/HP4, HP5, and now FP4+/HP5+.

Even those here in their 60's or 70's would have been using 3rd generation versions of Super XX & Trix-x in the 1960's and the Forte emulsions were based on the first generation launched in 1939. This is why comparisons show marked differences despite the common roots.

It's also worth remembering that even in the late 1960's there were still significant differences between some Kodak films depending on where they were made. Kodak UK developer data-sheets gave different times and recommendations for Tri-X depending on whether it was made in the UK, Canada or the US.

Kodak were still using older technology when their Hungarian factory began coating Super XX so it's unlikely to have been identical to the UK and US made versions.

Ian

Drew Wiley
22-Nov-2010, 10:36
Sandy - here you are making a blanket statement based upon one characteristic. For
projection printing, Bergger 200 could handle a very wide range of lighting conditions
and still provide excellent shadow differentiation and highlight control using pyro developers, without the severe graininess of Super-XX. The midtones can also be
marvelous. It's ability to do so relied upon a true straight line. Was it a replacement for Super-XX? Of course not. Nor is 400TMax. But for those of us who do projection rather than contact printing, these two films are remarkably versatile. Calling them "beginner" films might be acceptable if making life easier for folks trying to learn, but is a bit snide if you're implying there's anything unacceptable to advanced users in these films. I'm not belittling your persepctive as a contact printer
on long-scale media, which is valid in its own sphere, and could use a genuine replacement for Super-XX. But for projection printing, Bergger 200 was about as good
as it ever got. I won't go into rumors about why Super-XX was discontinued, other
than the commercial reasons for substitutions I've already noted, but perhaps someone
with a more immediate background to the story could. The environmental issue has
already been noted, which also killed off some favorite old papers. I belive cadmium
was a culprit in some cases, especially in the EU.

Michael Kadillak
22-Nov-2010, 10:56
Sandy - here you are making a blanket statement based upon one characteristic. For
projection printing, Bergger 200 could handle a very wide range of lighting conditions
and still provide excellent shadow differentiation and highlight control using pyro developers, without the severe graininess of Super-XX. The midtones can also be
marvelous. It's ability to do so relied upon a true straight line. Was it a replacement for Super-XX? Of course not. Nor is 400TMax. But for those of us who do projection rather than contact printing, these two films are remarkably versatile. Calling them "beginner" films might be acceptable if making life easier for folks trying to learn, but is a bit snide if you're implying there's anything unacceptable to advanced users in these films. I'm not belittling your persepctive as a contact printer
on long-scale media, which is valid in its own sphere, and could use a genuine replacement for Super-XX. But for projection printing, Bergger 200 was about as good
as it ever got. I won't go into rumors about why Super-XX was discontinued, other
than the commercial reasons for substitutions I've already noted, but perhaps someone
with a more immediate background to the story could. The environmental issue has
already been noted, which also killed off some favorite old papers. I belive cadmium
was a culprit in some cases, especially in the EU.

If photography could be assured as taking place within a predictable range of normal exposure and projection printing criteria then clearly your statements are on solid footing. All Sandy and several others (including myself) are adding to this post is a differing condition and perspective so that other interested parties that have differing visual criteria to express themselves have some compare and contrast information.

Please do not take these comments as anything more than honest opinions on the subject being bantered around. If you can attain optimal expression within your photographs with this or any other film, there is absolutely nothing wrong with that. There may be may others that take your comments and feel that there is commonality with how they may want to proceed. Similarly others may understand and appreciate differing opinions.

Cheers!

henrysamson
22-Nov-2010, 11:04
Can T-Max 400 be developed by inspection or does it still have the magenta dye?

BTW, I never remember Super-XX being all that popular in the 70's and 80's for general commercial/industrial large format photography. I used it for separations for dye transfer (still have some in my freezer . . . I think) but compared to the thin emulsion films it was not very sharp. Also I think I remember that it was somewhat more expensive than say Tri-X or Plus-X. The accepted reason was that it had more silver in it but I don't know if that was true or not.

Henry

Drew Wiley
22-Nov-2010, 11:14
Michael - it's all academic anyway, since both of these films are unavailable to new
purchasers. 100TMax is capable of a high degree of expansion, and will hold an almost
straight line in certain developers (but alas, has a totally different look than Super-XX).

sanking
22-Nov-2010, 14:01
Sandy - here you are making a blanket statement based upon one characteristic. For
projection printing, Bergger 200 could handle a very wide range of lighting conditions
and still provide excellent shadow differentiation and highlight control using pyro developers, without the severe graininess of Super-XX.

I considered BPF 200 a very mediocre film and stated why. It also had fairly coarse grain. That is not a blanket statement, but an opinion based on my criteria. However, the ability to do + development, which BPF 200 lacked, is not a problem only for contact printing. Anyone printing with a paper or process that has little or no contrast control, ie graded silver papers including AZO and Lodima, vandyke, etc. would be severely limited by the use of a film like BPF 200.

That said, I used a fair amount of BPF 200, and its brothers of a different name, J&C 200 and Forte 200. But all in all I classify it as a very mediocre film, which is not to say that people who used it were mediocre photographers or that good work could not be done with it given the right conditions.

Sandy

Michael Kadillak
22-Nov-2010, 14:07
Michael - it's all academic anyway, since both of these films are unavailable to new
purchasers. 100TMax is capable of a high degree of expansion, and will hold an almost
straight line in certain developers (but alas, has a totally different look than Super-XX).

True, but T Max 100 has a couple of things that need to be put into the correct perspective.

First T Max 100 has a UV coating on it that disqualifies it (or makes it very challenging) for any process using a UV as an exposure light source. We asked Kodak to leave this coating off of T Max 400 and they agreed to do so. Secondly, T Max 100 has a long history of optimal results favoring rotary processing and the consistency that comes from it. No necessarily a bad thing but it is a limiting condition that needs to be dealt with. Lastly is the look of the results and this is a personal judgement call.

There is no question that Super XX was a grainy film. But in contact prints this is not an issue. However that was then and this is now.

John Bowen
22-Nov-2010, 14:22
Can T-Max 400 be developed by inspection or does it still have the magenta dye?

Henry

Henry,

This reminds me of the question one of my math teachers used to ask; "did you walk to school today or bring your lunch?" :D

Yes, T-Max 400 can be developoed by inspection. I do it all the time, but I use an infrared monacle to do it. A Green Safelight won't work with T-Max 400. And, yes, T-Max 400 still has the magenta dye.

Happy Thanksgiving,

Drew Wiley
22-Nov-2010, 14:32
Michael - don't get the thing about 100TMax being optimized for rotary. It processes
superbly by other means too. Just a matter of the correct developer. A bit fussier than
some films in the highlights, but predictable. I've shot it in every format I own and am
quite comfortable with the film, though I don't like it for certain subjects and am aware
of the UV issue, though it doesn't affect me personally. My late brother left behind a
lot of Super-XX negs from the old days, and I hope to print a few of these eventually
because he is one of those folks who indulged in all kinds of tricks Super-XX was known for - reticulation, high-contrast grain enhancement, water bath, etc etc. I liked
it too, but have obviously moved on, then on again, then ...

Oren Grad
22-Nov-2010, 14:54
At the top of this thread (http://www.largeformatphotography.info/forum/showthread.php?t=10938), Christopher Nisperos cops to having invented the canard that BPF200 was a Super XX lookalike.

As Paul Butzi rightly points out later in the thread, this little fabrication wasted people's time, energy and money.

I tested BPF200 with D-76 and intensely disliked it. It combined a very abrupt shoulder with a sort-of-straight-line midrange that wasn't long enough to allow for decent shadow detail at any reasonable exposure. The only good results I ever saw from BPF200 - and there were some - were from other photographers who used pyro developers.

I remember discussing this with Phil Davis. Based on his own tests, he was appalled at the claim that BPF200 was more or less the same as Super XX.

Michael Kadillak
22-Nov-2010, 15:06
Michael - don't get the thing about 100TMax being optimized for rotary. It processes
superbly by other means too. Just a matter of the correct developer. A bit fussier than
some films in the highlights, but predictable. I've shot it in every format I own and am
quite comfortable with the film, though I don't like it for certain subjects and am aware
of the UV issue, though it doesn't affect me personally. My late brother left behind a
lot of Super-XX negs from the old days, and I hope to print a few of these eventually
because he is one of those folks who indulged in all kinds of tricks Super-XX was known for - reticulation, high-contrast grain enhancement, water bath, etc etc. I liked
it too, but have obviously moved on, then on again, then ...

I have some T Max 100 in the freezer. What developer and process works best for you? I am always game particularly when I am sitting on the materials.

sanking
22-Nov-2010, 15:22
I remember discussing this with Phil Davis. Based on his own tests, he was appalled at the claim that BPF200 was more or less the same as Super XX.

And Phil also observed that BPF 200 was not a true ASA 200 film, and he was correct. I tested it several times with tight sensitometry controls and it always came out about ASA 100, as Phil had found.

What irks me about all of this is the deliberate misrepresentation of the film as a SuperXX "lookalike'. That was simply untrue, unless you were comparing BPF 200 to Super XX from the 1940s or 1950s as Ian has suggested, but in 2000 who would have been doing that?

Sandy

IanG
22-Nov-2010, 15:37
Oren, the current Volkswagen Golf is quite different to the first Golf of 1974, yet both are related and carry the same name.

This is why Fortepan/Bergger 200 could be claimed to be similar to Super XX, because it was a direct descendant of the Kodak film and made in a former Kodak plant with ex Kodak equipment & technology.

The mistake is that people dismiss the claim without understanding or realising the background.

Perhaps dodgy marketing in the US made some people think the Fortepan 200 it would be similar to the the last generation of Kodak's own Super XX, and one company in particular were to blame. However in the UK and EU the Forte films were sold as old style thick emulsions with no hype except when sold by Bergger.

Ian

Drew Wiley
22-Nov-2010, 16:07
A combination of replies: I have been rating Bergger 200 at 200 ever since it came out
and have gotten superb shadow separation well down into Zone I or below. PMK. This
seems to mimic the results Gordon Hutchings got when he called it the best marriage
of film and developer ever in his own experience (again, for projection printing). 76 developer will throw a slight bow into the curve, and a distinct one into 100TMax. For
color sep work I use a modified version of TMax RS with a toe-cutter in order to get
something very close to a straight line way down into the shadows. The extent of this testing was way beyond anything I might contmplate for general use, including three completely different filtration systems. For general shooting I develop both T-Max films in PMK, though I have tested certain other pyrog and pyrocat formulas with decent results. Have done similar tests with 400TMax and FP4+.

sanking
22-Nov-2010, 16:32
Perhaps dodgy marketing in the US made some people think the Fortepan 200 it would be similar to the the last generation of Kodak's own Super XX, and one company in particular were to blame. However in the UK and EU the Forte films were sold as old style thick emulsions with no hype except when sold by Bergger.

Ian


OK, that is probably true since the only untrue hype I saw came from representatives of Bergger who suggested that BPF 200 was especially made with a Bergger formula, and thus different from the less expensive Forte 200 and J&C 200 sold in the US. That claim was simply false and totally misleading.

Sandy

Drew Wiley
22-Nov-2010, 16:40
Sandy - I found that true with Bergger in general. A bit of marketing BS. But I first
purchased the Fortepan 200 film under the Lotus label, which never made the claim of
it being a direct substitute for Super XX. What I don't know is true of not, is the claim
some supposed insider made that all the later batches of Super XX were in fact made
in E Europe using very antiquated equipment which simply didn't match Kodak's long-range plan for modular mfg.

Oren Grad
22-Nov-2010, 17:00
Oren, the current Volkswagen Golf is quite different to the first Golf of 1974, yet both are related and carry the same name.

True, but people shopping for a Super XX "clone" at the time BPF200 was marketed were looking to replace the film they'd been using, not the film that somebody else used 40 years earlier. That bit of marketing by Bergger was flat out misleading.

FWIW, I didn't have any problem with Forte's own marketing. And although I strongly disliked the ISO 200 film, I found their ISO 400 sheet film as well as all of the Forte papers that I tried to be perfectly usable and useful products. I used to keep a stock of Polygrade V on hand along with the other papers I use.

Drew Wiley
22-Nov-2010, 17:23
Oren - I find it hard to believe that BPF200 was an old formula. I was just too fine-grained for an old-style film, and could only marginally be classified as thick emulsion.
The quality control was superb. Just the opposite of you, I hated the Forte 400 and
loved the 200. Guess we both agree about Polygrade V, however. I still have a large box of 20x24 and use it for certain images, although I'm getting even better results now with Kentmere Fineprint (after a distinct new learning curve).

Oren Grad
22-Nov-2010, 17:32
The quality control was superb.

Oy. I bought several boxes of BPF200 cut for whole plate. The whole batch suffered from the "corrugated skies" emulsion defect that results from stuttering in an improperly adjusted coating machine. The BPF200 experience was just a big downer for me, all around.

Anyway, that's all history. Now that I can get factory-cut HP5 Plus in all the sizes I like to use, I'm happy.

IanG
22-Nov-2010, 17:51
Luckily I still have a few hundred sheets of Forte Polywarmtone left, well maybe not so many but larger sizes which I can cut down to give me more of the size I mainly use :D

I found to my surprise last Spring that I still have 3 boxes of 10"x8" Fortepan 200 (actually Classic Pan 200), the labelling is rather small and indistinct - I'd assumed it was EFKE PL25. My experiences is that it's a really nice film but then I never tried Super XX it's not been available here in the UK for decades, it had gone before I became a serious photographer in the mid to late 60's.

Fortepan 200 may well have been tweaked in it's last coatings, I'm hyper critical but liked it, however I wouldn't have used it in 120 or 35mm.

it's hard making a way through manufacturers or rather distributors hype, I always found Forte 100% accurate, and Fotoimpex.

Ian

Drew Wiley
22-Nov-2010, 20:03
Oren- I sure would be curious where you got that film. A coating defect wouldn't show up on a single size of film, since it all comes off a master roll, unless it was the cutting machine rather than coater at fault. Was the film interleafed with paper? Forte had such a strong reputation for consistent product that it is all that the commercial labs around here would use in their heyday. (I have had one pack of warmtone Polygrade which had some minor coating issues.)

Oren Grad
22-Nov-2010, 20:29
Oren- I sure would be curious where you got that film. A coating defect wouldn't show up on a single size of film, since it all comes off a master roll, unless it was the cutting machine rather than coater at fault. Was the film interleafed with paper? Forte had such a strong reputation for consistent product that it is all that the commercial labs around here would use in their heyday. (I have had one pack of warmtone Polygrade which had some minor coating issues.)

It was Bergger-labeled film obtained through John Horowy, who was Bergger's US representative. Yes, it came with interleaving. There's no question it was a coating defect. No, I wasn't the only user and WP wasn't the only size to have a problem - at least one master roll was indeed faulty; probably more.

No need to sweat it, especially since Forte is gone now. If you never had a problem, just count your blessings and enjoy all the good pictures you were able to make.

Drew Wiley
23-Nov-2010, 11:37
Thanks Oren. Something like that would have pissed me off too. I surprised they let a
batch like that even get packaged. In general I haven't been too fond of EU packaging.
For example, I learned the hard way never to reuse film boxes because they aren't light
tight, and rely on the inner plastic bag.

keith schreiber
23-Nov-2010, 22:24
I had a similar experience with 4 out of 6 boxes of 7x17 BPF200 in 2007. (The other 2 were a different emulsion batch and were fine.) Unfortunately for me it was on a 4 month road trip and I only discovered the problem after it was too late. When I finally developed the film a few months later, thought it had to be some processing error on my part. About a year later I came across another guy on the B&S forum who had the same problem with the same film. Cold comfort.

You described it as "corrugated skies" which to me sounds like a fairly regular pattern. Mine was a bit more irregular with more curvy or wavy lines. It afflicted about 80% of the 7x17 film that I exposed on my journey to Newfoundland.

As a curious aside, more recently I had an eerily similar issue with digital negatives printed on one particular batch of Pictorico OHP. I typically allow the digital negs to "cure" for 24 hours or so before use or storage. What I found was after being stored in paper folders for as little as a day (the same way I have been doing it for years), it appeared that the paper absorbed some residual moisture from the film and became wrinkled which resulted in bands or more or less density following the same pattern as the wrinkles in the paper.

I mention this because after it happened I suddenly remembered having noticed that the interleaving tissue from the Bergger 7x17 film had also been wrinkled. I didn't think anything of it at the time.

The two things may or may not causally be related, but the visual effect is similar.