More Fomapan 400 120 defects

[GregY]

Ahhhh another case of bad backing paper? Not surprising… this is why I don’t use their paper. I have a ton of it though and I have no clue what to do with it.

From what I can tell, the issue is that unlike all manufacturers of 120 paper today, including Shanghai now, Foma use a single-ply paper with a dark ink applied to one side instead of a plastic membrane glued to the paper. This ink does not appear to be chemically inert, at least not consistently. To fix it, Foma would need to completely redo their backing paper, which I suspect they see as being economically infeasible.

Foma enlarging paper has shown none of the QC inconsistencies that have plagued their films...
It's one of the few companies still producing paper & they print beautifully.

 

[MCB18]

Foma enlarging paper has shown none of the QC inconsistencies that have plagued their films...
It's one of the few companies still producing paper & they print beautifully.

I am not referring to enlarging paper here, I am referring to the backing paper used on rollfilm, that has been consistently problematic for Foma for a while now. Even other companies who use Foma as a finishing partner have been having these issues. Rollei 80S had this exact same problem not so long ago.

 

[GregY]

I am not referring to enlarging paper here, I am referring to the backing paper used on rollfilm, that has been consistently problematic for Foma for a while now. Even other companies who use Foma as a finishing partner have been having these issues. Rollei 80S had this exact same problem not so long ago.

i was mislead by your phrase "this is why I don’t use their paper"

 

[MCB18]

i was mislead by your phrase "this is why I don’t use their paper"

Yes, I have a bunch of foma backing paper that I don’t use when making 120/220 because it is extremely problematic.

 

[John Wiegerink]

Ahhhh another case of bad backing paper? Not surprising… this is why I don’t use their paper. I have a ton of it though and I have no clue what to do with it.

From what I can tell, the issue is that unlike all manufacturers of 120 paper today, including Shanghai now, Foma use a single-ply paper with a dark ink applied to one side instead of a plastic membrane glued to the paper. This ink does not appear to be chemically inert, at least not consistently. To fix it, Foma would need to completely redo their backing paper, which I suspect they see as being economically infeasible.

The problem is NOT an ink, dye, numbers transfer thing. It's more a fungus problem with the OP's film. The problem with Foma 200 is an emulsion problem or a compatibility problem between the emulsion and backing paper, but NOT number transfer or offset.

 

[GregY]

Yes, I have a bunch of foma backing paper that I don’t use when making 120/220 because it is extremely problematic.

Ah.... not many folks roll their own 120/220. Got it
I don't use Foma films exactly because of their QC issues.
Ilford get my $$

 

[MCB18]

The problem is NOT an ink, dye, numbers transfer thing. It's more a fungus problem with the OP's film. The problem with Foma 200 is an emulsion problem or a compatibility problem between the emulsion and backing paper, but NOT number transfer or offset.

Again, the ink on the back of the paper seems to be the issue, not the numbers on the white side. Why this is I am not sure, possibly they use 2 different inks to ensure that the paper is light tight. Either way, it is way too consistent across the entire roll, not to mention multiple rolls, in multiple batches, over years, to be any fungus.

 

[John Wiegerink]

Again, the ink on the back of the paper seems to be the issue, not the numbers on the white side. Why this is I am not sure, possibly they use 2 different inks to ensure that the paper is light tight. Either way, it is way too consistent across the entire roll, not to mention multiple rolls, in multiple batches, over years, to be any fungus.

OK, gotcha!

 

[MattKing]

Again, the ink on the back of the paper seems to be the issue, not the numbers on the white side. Why this is I am not sure, possibly they use 2 different inks to ensure that the paper is light tight. Either way, it is way too consistent across the entire roll, not to mention multiple rolls, in multiple batches, over years, to be any fungus.

It is important to remember that it is the side of the backing paper that has the numbers on it that the (next layer of) the film emulsion actually comes in contact with.
The black side of the paper is pushed against the film substrate, not the emulsion.
Unless the film is one of the rare films that has something added (anti-halation?) to the back of the substrate, there isn't much that can react with the black side of the paper.

 

[MCB18]

Unless the film is one of the rare films that has something added (anti-halation?) to the back of the substrate, there isn't much that can react with the black side of the paper.

I believe that Foma does have the antihal on the back as a matter of fact. And Aviphot (as in 80S) definitely has the antihal on the back of the film.

Edit To Add: yes, Foma does put an antihal gel on the back of the film. From the datasheet:

120 rollfilm - a clear polyester base 0.1 mm thick, furnished with an antihalo colour backing which will decolourize during processing.

 

[koraks]

The black side of the paper is pushed against the film substrate, not the emulsion.

Compounds from the ink can (and will) still migrate through the paper base, however.

Unless the film is one of the rare films that has something added (anti-halation?) to the back of the substrate

That's not rare; it's pretty much standard that there's an anti-curl gelatin layer on the backside of 120 film. And indeed, in Foma's case, anti-halation dye is included in that layer.

 

[MattKing]

at's not rare; it's pretty much standard that there's an anti-curl gelatin layer on the backside of 120 film. And indeed, in Foma's case, anti-halation dye is included in that layer.

Is that likely though to react with the ink on the black side of the paper or anything else on that side of the paper in a way that will survive the development process without washing away?

 

[MCB18]

Is that likely though to react with the ink on the black side of the paper or anything else on that side of the paper in a way that will survive the development process without washing away?

I’d say based on this and several other cases of similar mottling… yes. I’m no chemical engineer, but I think it’s a safe assumption that something in that ink reacts with something on the film they put in that paper.

How or why I couldn’t tell you, but there’s a pretty big correlation between the paper and these issues that no other manufacturer has had since what, 2020 when Ilford had a very similar issue and confirmed it to be a backing paper issue? And before that, besides Foma, it was Kodak having issues after outsourcing their paper around 2012…

 

[MattKing]

I’d say based on this and several other cases of similar mottling… yes. I’m no chemical engineer, but I think it’s a safe assumption that something in that ink reacts with something on the film they put in that paper.

How or why I couldn’t tell you, but there’s a pretty big correlation between the paper and these issues that no other manufacturer has had since what, 2020 when Ilford had a very similar issue and confirmed it to be a backing paper issue? And before that, besides Foma, it was Kodak having issues after outsourcing their paper around 2012…

I don't disagree.
I just have doubts about it being that side of the paper - the side that isn't in contact with the emulsion of the film.

 

[koraks]

Is that likely though to react with the ink on the black side of the paper or anything else on that side of the paper in a way that will survive the development process without washing away?

No, I agree; the silver halide-carrying emulsion layer is inherently more sensitive!

 

[khh]

You could have dye transfer from the black layer of the backing paper to the anti-curl/anti-halation layer on the back. That dye isn't water soluble, so if it were to transfer it wouldn't be washed out during processing.

 

[MCB18]

You could have dye transfer from the black layer of the backing paper to the anti-curl/anti-halation layer on the back. That dye isn't water soluble, so if it were to transfer it wouldn't be washed out during processing.

Definitely possible. Dye transfer is a thing and can be annoying even in another hobby completely unrelated to photography. I have gotten used stuff that had black dye/pigment transfer stains from the storage totes they were stored in, impossible to wash off. And they’re just regular PVC, not any special material or anything.

 

[Harry Callahan]

And just like in the other thread, I'm going to tell you again that your theory doesn't add up. Pressure marks show up as higher density. You can easily try this with any silver gelatin material. Mar with your fingernail, then develop. If you take any roll of film, noteice how the very edge tends to be black after processing; this is where the film was cut and the pressure of the blade has rendered the silver halides along the very edge developable. It takes a fair bit of force to get silver halides to respond to pressure.

...

In case you`re interested, i found something by accident which could support my theory - though it is related to Foma 200:

"FOMAPAN 200 Creative emulsion contains T-crystals providing high resolution and
very low granularity of the film. Relating to this it may emerge its higher sensitivity to
mechanical strain mainly during movement of the rollfilm throughout some middle-
format cameras. That may result in occurrence of desensitization records on
developed negative."

https://www.foma.cz/en/fomapan-200

 

[Rayt]

I only shoot Kodak roll film because of disappointing experience with backing paper defects with Foma, Rolli 80, Shanghai and other Chinese films, also a batch of Ilford HP5+. I shoot all of the above in other formats so nothing against the emulsions themselves. Imagine coming home from a week long trip to Saigon with unusable images. I’ll shoot Ilford since I am sure it was an one off. This is from the Chinese film but I don’t remember the brand:

 

[Harry Callahan]

Well, i am talking about defects not related to the backing paper but mechanical strain.

 

[John Wiegerink]

In case you`re interested, i found something by accident which could support my theory - though it is related to Foma 200:

"FOMAPAN 200 Creative emulsion contains T-crystals providing high resolution and
very low granularity of the film. Relating to this it may emerge its higher sensitivity to
mechanical strain mainly during movement of the rollfilm throughout some middle-
format cameras. That may result in occurrence of desensitization records on
developed negative."

https://www.foma.cz/en/fomapan-200

Whoa, I don't remember seeing or reading that statement, but I believe that that is entirely true. Unfortunately that strain happens with every medium format camera I own. Just a note, the Foma film I mentioned buying above ended up being faulty in several cameras and with every roll I bought. What a shame!

 

[Harry Callahan]

Do you also own some "classical" folders? I can get that there is strain on the film in a Hasselblad-style magazine, but an (older) folder should be more gentle to the film...

 

[koraks]

In case you`re interested, i found something by accident which could support my theory - though it is related to Foma 200:

Attaboy. If you've seen Foma 200 in 120 format and the defects it produces, you'll notice it's a fundamentally different phenomenon than what we're talking about here.

 

[Harry Callahan]

I brought this up because i once had the theory that pressure on the emulsion could create lower density on the negative. You said pressure only does produce higher density.

 

[koraks]

I'm aware of the "I said, you said" etc. I'm also aware of the issue reported here and how it's not a pressure issue, so at this point we're working at the level of you having a hypothesis that doesn't apply here, but you're trying to conjure up some credibility for it, because...well, IDK why really.

Your interpretation of Foma's quote is moreover doubtful. Firstly, we're looking at a low-quality translation into English and we're left to guess at what the Foma people were trying to say in the first place. Insofar as what they committed to paper in the datasheet, it doesn't specifically mention 'pressure'. It refers to 'desensitization records' (whatever the heck that may mean) due to mechanical strain. What we KNOW about this film specifically in 120 format is that it can experience emulsion cracking resulting in sharply defined marks that run along the length of the film and that appear to be tiny little fractures or cracks in the actual emulsion. They show up as dark on the processed image, so are lower in density in the negative image. I can see how you specifically (given confirmation bias; you're only human) interpret this as 'reduced density due to pressure', but I personally don't think that's necessarily a good way of putting it.

Secondly, emphasizing that if you have actually used the product and have witnessed the defects, both in your own work and that of others, you'll recognize why I'm hesitant to recognize the relevance of all this to the present thread. Here's some of the defects that are typical for Fomapan 200:

Scuff marks in the emulsion

"Peppercorn" inclusions

Samples from this very film were sent to Foma who responded with a literal "it's not you, it's us" and they sent me replacement films - which suffered from the same problems.
Nothing in this suggests it's pressure related. I know the story about "some cameras destroy this film". Empirical testing friends of mine have done as well as me, personally, showed no correlation between film transport mechanism and the appearance of these defects. This is the umpteenth time I've relayed this story over the past decade and even today I see the same defects pop up on this particular film as well as people who have not seen it argue about how it doesn't exist, is caused by stop bath etc.

In theory a film like Fomapan 200 could be more sensitive to physical disturbance because it's a semi-tabular grain emulsion and the result is that the grains (1) have a high aspect ratio; i.e. they're more like little flapjacks than tiny little breadcrumbs, and (2) they are oriented all in the same way. This physical arrangement makes it at least in theory easier for stress cracks to develop in the emulsion, especially if there are contributing factors like a brittle emulsion to begin with and imperfect subbing of the film support. I can see how all this could work its way into the awkward and technically dubious formulation you picked from the Fomapan 200 datasheet. That still doesn't support "pressure creates low density anomalies" since not all mechanical strain is pressure, and not all low-density defects result from desensitization. Besides, anyone who has inadvertently pressure-damaged their film due to kinking, dragging across a blunt protrusion etc. is aware of the fact that pressure will result in density on the negative.

Show me empirical examples combined with a decent explanation that holds water and then maybe we can talk. And please, if you do so, start a new thread on it as it has nothing to do with what this thread is about.