More Fomapan 400 120 defects

[Harry Callahan]

Sigh, i said right from the start that this desensitization does apply to Foma 200. I did not claim it to apply for Foma 400. Also i did not claim it to be the reasons for the Foma 400 problems in this thread here - all i said was that with Foma 200 apparently mechanical strain can lead to desensitization.
I am aware that "strain" does not equal "pressure", though i looked in a dictionary where about the last entry did translate "strain" by "pressure" - so far fetched they also could be talking about pressure, but the paper is vague on that.
But the paper makes it seem like it is the T-grain which does react by fewer density when strain is applied to the film.
I am aware that Foma 200 is the only film having T-grain.
I don`t consider emulsion cracks "reduced density due to mechanical pressure" and never said so.

If the reason for Foma 200 having these problems was emulsion cracks, it would be easier to put this in the paper - and advice people to only use medium format cameras where the film does not make tight turns, like in a Hasselblad magazine for example. If the reason was emulsion cracks this film should be unproblematic in an old folder for example - but as i read from your statement it is not related to film travel through the camera.

As we did not talk about pressure on emulsion in a thread about Foma 200, i put my finding in a thread where we were talking about pressure on emulsion - like this thread here.

I don`t have empirical evidence, i probably couldn`t provide a waterproof explanation even if the effect was real - i wanted to add my finding to a thread where we were talking about the possibility of mechanical pressure to maybe add something useful.

But you keep on interpreting that
- i am talking about Foma 400
-i believe this to be the reason for the problems of 400 discussed in this thread
-i`m trying to conjure credibility for my theory
-i consider strain to be the same a pressure
-i consider emulsion cracks to resemble reduced density
-and whatever

- and that`s why i feel like talking in a foreign language for example. People interpret a whole bunch of stuff into a statement of mine - including a lot of things i never said. And if i do state for days, over and over again, that i am talking about enlarging only - several believe that i am talking about shooting and answer related to shooting pictures.

 

[John Wiegerink]

Sigh, i said right from the start that this desensitization does apply to Foma 200. I did not claim it to apply for Foma 400. Also i did not claim it to be the reasons for the Foma 400 problems in this thread here - all i said was that with Foma 200 apparently mechanical strain can lead to desensitization.
I am aware that "strain" does not equal "pressure", though i looked in a dictionary where about the last entry did translate "strain" by "pressure" - so far fetched they also could be talking about pressure, but the paper is vague on that.
But the paper makes it seem like it is the T-grain which does react by fewer density when strain is applied to the film.
I am aware that Foma 200 is the only film having T-grain.
I don`t consider emulsion cracks "reduced density due to mechanical pressure" and never said so.

If the reason for Foma 200 having these problems was emulsion cracks, it would be easier to put this in the paper - and advice people to only use medium format cameras where the film does not make tight turns, like in a Hasselblad magazine for example. If the reason was emulsion cracks this film should be unproblematic in an old folder for example - but as i read from your statement it is not related to film travel through the camera.

As we did not talk about pressure on emulsion in a thread about Foma 200, i put my finding in a thread where we were talking about pressure on emulsion - like this thread here.

I don`t have empirical evidence, i probably couldn`t provide a waterproof explanation even if the effect was real - i wanted to add my finding to a thread where we were talking about the possibility of mechanical pressure to maybe add something useful.

But you keep on interpreting that
- i am talking about Foma 400
-i believe this to be the reason for the problems of 400 discussed in this thread
-i`m trying to conjure credibility for my theory
-i consider strain to be the same a pressure
-i consider emulsion cracks to resemble reduced density
-and whatever

- and that`s why i feel like talking in a foreign language for example. People interpret a whole bunch of stuff into a statement of mine - including a lot of things i never said. And if i do state for days, over and over again, that i am talking about enlarging only - several believe that i am talking about shooting and answer related to shooting pictures.

Harry,
I don't seem to have much of a problem with either Foma 100 or 400, but have relegated Foma 200 just for testing repair cameras out just in hopes that one of those "just repaired cameras can eliminate those tiny little emulsion cracks. So far none have and even my older straight run folder can't seem to stop those little gremlin cracks from showing up. It must just be my luck or maybe the way I hold my mouth when I trip the shutter or wind the film on.

 

[Harry Callahan]

I see, thank you for the answer.

 

[Thomas Bertilsson]

Waking up an old thread here, just reporting that I had a batch of Fomapan 400 in 120 format that had the same problem it has had in the past with an imprint of the backing paper on the film. I had 20 rolls, out of which I used 11. Batch number 011756 5. Expiration date November 2025.
- Rolls of other brands developed alongside were fine (Kentmere 400, Ilford HP5+)
- Three different developers used (D76 1+1, Paterson FX-39 1+9, PMK-Pyro) makes no difference on the outcome
- Presoak and no presoak makes no difference on the outcome

My advice would simply be to only use this film from a batch you for sure have tested, and within a short time of testing it. The problem seems to get worse the longer the film sits unused.
It has ruined dozens of rolls for me over the last years. I absolutely love how the film looks once processed and printed, but the extra step of having to test the 120 film each time is very tiring. The attached picture is one example from a contact sheet, there are those that are a little bit better, and those that are a bit worse.

 

[koraks]

Oh yeah, that's classic. You're right that the risk & impact get bigger the older the film is, with storage conditions being an important moderating variable.

 

[Thomas Bertilsson]

Oh yeah, that's classic. You're right that the risk & impact get bigger the older the film is, with storage conditions being an important moderating variable.

Normal room temperature should be OK for b&w films, kept in their wrappers until shooting them, and processing within a few days should be good enough.
No issues with Kodak, Ilford, or Kentmere under the same conditions, even outdated film of other brands don't behave like this.

 

[Craig]

Waking up an old thread here, just reporting that I had a batch of Fomapan 400 in 120 format that had the same problem it has had in the past with an imprint of the backing paper on the film.

Is that caused by the backing paper, and only the backing paper?

I ask because once a friend put his film in his checked bags when flying and got a similar pattern from X Rays. This was probably 20 years ago before wrapper offset was a problem.

 

[Thomas Bertilsson]

Is that caused by the backing paper, and only the backing paper?

I ask because once a friend put his film in his checked bags when flying and got a similar pattern from X Rays. This was probably 20 years ago before wrapper offset was a problem.

To my knowledge yes. On some frames one can see the imprint of the ink on the backin paper as well, like the round dots and the numbers. I usually travel by train if I go somewhere to photograph, and this film has not been flying.

 

[koraks]

got a similar pattern from X Rays

No way. Sorry.

 

[albireo]

Normal room temperature should be OK for b&w films, kept in their wrappers until shooting them, and processing within a few days should be good enough.
No issues with Kodak, Ilford, or Kentmere under the same conditions, even outdated film of other brands don't behave like this.

I've never had these backing paper mottling issues with Foma 400 (and until last year this was my main 120 high speed film, I used hundreds of rolls per year), but I did with lightly expired Ilford, Rollei and Foma 100 (not 400) film kept at room temperature.

How do the Americans say? It's a 'crapshoot'.

The sad reality is that film, any film, in 2025, should be used strictly within its due date.

Just purchase film that you know you'll be using over the next 2-3 months and you'll be fine.

 

[Thomas Bertilsson]

I've never had these backing paper mottling issues with Foma 400 (and until last year this was my main 120 high speed film, I used hundreds of rolls per year), but I did with lightly expired Ilford, Rollei and Foma 100 (not 400) film kept at room temperature.

How do the Americans say? It's a 'crapshoot'.

The sad reality is that film, any film, in 2025, should be used strictly within their due date.

Just purchase film that you know you'll be using over the next 2-3 months and you'll be fine.

Foma in 120 format is the only film I have consistently had problems with. If I go through my records, I have had Ilford Pan-F 120 (before the plus days) that was expired, and some very expired Agfa APX25. Other than that, Fomapan 200 and 400 in 120 format have been a massive headache for me. When I wrote the shop here in Switzerland where I buy it, they acknowledged that I was not the only one, that there had been some significant problems this year. Make of it what you want.

Nowadays I always buy fresh film, this batch of Fomapan 400 was purchased towards the end of 2024, so there was a year to go before the expiration date. I was hoping that my information regarding the specific batch and expiration date could be helpful to some, to not have the same misfortune.

 

[halfaman]

Foma 400 is my test roll film for any new camera trying to introduce into my herd. So far I had no quality issues, but I would not mind it either.