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.