Hitting nail on head!
Originally Posted by Thomas Bertilsson
I think I made some progress today. I developed three ‘no-camera’ Foma 100-120 films.
The first film was first unrolled to its full length (no cameras involved) and then exposed to a couple seconds of the artificial lighting in my darkroom. This film showed no scratches at all. This rules out as a cause for the scratches the entire chemical stage from developing onwards. Instead the problem seems to be with the camera or some other form of mechanical abuse during handling before or after exposure. This abuse could be my method of loading the film into the reels of the developing tank.
What I do is that I put the film in an old medium format camera (Agfa Clack) and then pull out the film and wind it up the reel (see picture in attachment). Something that never occurred to me before is that during this process, the paper backing curls up against the film and slips against it. This ‘brushing’ of the film does not seem to involve much force. However, the backing is rather rough and stiff (much stiffer and rougher than the paper from the big brands). It’s not exactly sandpaper, but in relative terms it is (see close-up in attachment). It seems entirely possible that the rubbing causes the scratches.
Unfortunately I do not have my cameras (apart from the Clack) in the location of my darkroom. (My darkroom is in my parents’ house and I live 15 km away from there in a place too small for a darkroom.) Therefore I could not load a film into any of the cameras that I normally use and that gave me the pictures with scratches.
I loaded a film into the Clack instead and wound that onto the take-up spool, in order to simulate the forces that the film feels in the other cameras. Then I loaded the film into the developing reel, just like with the previous film, i.e. with the ‘sandpaper’ rubbing against the film. I did the loading in daylight so that the film got its exposure.
This film did show scratches, identical to the ones I had before. Interestingly, the scratches were not homogeneously spread over the film, but grouped in batches a few centimetres apart from each other.
Did the scratches come from the rubbing of the backing paper against the film or from friction during transport inside the camera?
The third film I wound onto an empty spool first, very gently and by hand, not inside any camera. Then I put that second spool into the Clack and loaded it into the developing reel from there, i.e. with the paper backing rolling/rubbing against the film. In addition I extra-rubbed the backing paper against the last part of the film, like when using sandpaper on wood or something.
This film also showed scratches, but no extra scratches where I extra-rubbed the film. Maybe I rubbed the wrong side of the film?
The conclusion from this last film seems to be that the rolling/rubbing of the backing paper against the film (as in the first attachment) is enough to produce scratches. The question is now if a film that was wound/exposed inside a camera will show scratches even if the backing paper never rubs against it like in the picture.
Tomorrow I will shoot a film inside a camera (Hasselblad 500cm) and develop it. If it shows scratches then those are caused by transport (friction) of the film inside the camera. If it doesn’t show scratches then my reel-loading method (where the backing paper rubs against the film) is to blame.
What to think of all this? Fomapan 100-120 seems a very vulnerable film, a bit too much so I think. Even if I manage to eliminate the cause of the scratching then will I ever have full confidence that they won’t show up again at some unfortunate moment? Why does Foma use backing paper that is so rough? I just did a little test: if I rub Foma backing paper against Foma film then that film is very visibly damaged, but if I do the same thing with Fuji backing paper against Foma film then the film is completely undamaged. This Foma backing paper really is a liability.
I will post more results tomorrow (for myself and for those interested in more scratches).
I too always thought that the backing paper was unnecessarily rough on the film itself. I also have a concern that it might wear out the mechanics of my Hasselblad film backs prematurely as there is a fair amount of abrasion going on.
Keep us posted. Your findings are very interesting.
"Often moments come looking for us". - Robert Frank
"Make good art!" - Neil Gaiman
"...the heart and mind are the true lens of the camera". - Yousuf Karsh
Hasselblad eaten by paper, that's quite funny. But you may be right of course, this stuff really is a bit like sandpaper.
Originally Posted by Thomas Bertilsson
Interesting dialpgue here. Could this abrasive paper also be where 'static' charge marks are making there way onto the film, or are they actual scratches...??
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I don't know enough about the static marks to tell if they could be caused by some property of the backing paper. I am under the impression that my scratches are actually true scratches, i.e. holes in the emulsion as a result of mechanical action.
Originally Posted by Andrew Moxom
I should try another 'no-camera' film where I rub both surfaces with the backing paper, before I develop the film. The rubbing does visibly (with the naked eye) scratch the surfaces of the negative- I have seen that. But I would also like to see damage to the emulsion itself in the same places. That would confirm unequivocally the paper's 'potentially destructive nature'
When I load my reels, I slit the tape, unroll it between my two hands until I reach the beginning ( last frame) of the film. I hold the film by the edges, and let the paper backing and spool fall to the floor (hang on tight! it's a bugger to find the roll if you drop it). I leave it attached by the tape at the end of the film to provied some weight to keep the film taught as I feed it into the paterson plastic reel. I walk the film into the reel until the taped end is close to the reel, then tear off the backing paper and spool, and wind the rest of the film into the reel.
"I'm still developing"
Thanks Rick, that's more or less how I intended to do it today. One of the reasons for me to previously load from a 'dummy-camera' has always been the fear of accidentally dropping the film. Being a bit clumsy I remember that I had that some time- no fun.
About the rubbing of the backing-paper : one might not forget that during transport, there is some friction between the film, be it on the emulsion side or not, and the famous paper. Rolling two ‚bands’ on one axle is always causing a kind of friction between them due to the slight but present difference of winding speed. Also, in the Hasselblad (the camera I shoot the most with); the film, in the transport system, is turned inside—out on the unrolling side, and then turned inside—in on the take up side. This means that there are two movements in opposite way of the two bands, the film and the backing-paper. Not to mention the passing over the flattening rolls and the pressure-plate.
Then, add the handling for processing, and there you have a chain of friction-scratching-brushing and alike, that the Foma film might not like.
I too, I did like the way the Bohemian emulsion ‚saw’ the subject, and I do like a rather present but beautiful and ‚pinned’ grain. But it did not work out. That’s why I had to move, with some pain in the hart, to the Rochesterian emulsion.
I found the Foma 100/400 — Pyrocat H-D combo to be rather close to the Agfapan 100/400 — Rodinal combo. But, of course, this last point is a very, very, personal opinion…
"...If you can not stand the rustle of the leafs, then do not go in to the woods..."
(freely translated quote by Guido Gezelle)
PS: English is only my third language, please do forgive me my sloppy grammar...
I developed this morning a film shot in the Hasselblad two days ago. I made sure that the rough paper backing did not contact the film while loading it into the developing reel.
Unfortunately the film shows the same pattern of scratches that did all the other ones exposed inside a camera. The only film so far that did not show scratches was the one that 1) was never loaded onto a take-up spool and that 2) never contacted the backing paper in any abrasive way.
The fact that I managed to produce one film without any scratches whatsoever means that the chemical stage (developing/fixing etc.) can be excluded as a cause for the scratches. Today’s result leaves only the camera. Something happens in the camera that causes the film to be scratched. To be precise, something happens in three cameras (Rolleiflex 3.5F, Hasselblad 500 CM, Agfa Clack).
The difference between a film that is never wound onto a second spool inside a camera and a film that is, to me seems to lie in the contact between backing paper and film. My theory is that the backing paper moves relative to the film, touches it, and thus scratches it. I imagine that the following takes place inside the camera during transport of the film from the one frame to the next:
The backing paper is always slightly farther from the centre of the spool than the film itself. However, the spool rotates at one certain angular speed, determined by the camera operator. Therefore, when the film is transported over length x, the backing paper is transported over a distance slightly larger than x.
This is a small difference, but not negligible. If you do the math (assuming a film thickness of 0.1mm, a paper thickness of 0.05mm, a spool-plus-film radius of 5mm and a translation of 60mm) you end up with a relative displacement of the order of 1mm. Such a ‘slack’ in the backing will be too little to interfere with film flatness.
When film and backing paper are re-united on the take-up spool, the slack goes out again. This goes accompanied (again) with the film and paper moving relative to each other. If, during this movement, film and paper are pressed onto each other, as is the case on the take-up spool, the rough surface of the paper may draw small marks onto the film. These lines would run along the length of the film, would not be entirely homogeneously spread over the surface of the film (because speed of transport is not constant), and would be equal to or smaller than the 1mm stated above.
My scratches are about 0.2mm in length, they appear grouped instead of entirely homogeneous and they run along the length of the film.
It’s just a theory and it’s the best I can come up with to explain the scratches. Maybe it’s no more than far fetched bogus. But if it is true then it seems that I can do little about it.
Also, if true, one would expect everybody to observe the same scratches, since I do not transport the film in any special (rough) manner (I think). But I appear to be the only one to have this problem.
Something that I must do and have not done yet, is to rub the backing paper against both surfaces of a test film, develop that film and see if the rubbing has caused a local increase in ‘scratches-density’. I did earlier rub the paper against one side of the film, and did not see any increase. I should try again and on both sides of the film. I will try this tomorrow, hopefully.
One other thing about Foma 100 in 120, having nothing to do with the silly scratches: it is shorter than any film I have tried before. In fact it barely fits 12 frames (see attachment).
When I align the arrow on the backing paper with the arrow in the camera, then the last frame drops off the film, or about 1cm of it. So what I do now is that I wind the film slightly less far onto the take-up spool before closing the back and winding on to frame one. I leave about 2-3cm in between the arrow on the paper and the arrow in the camera.
I guess this is how Foma gets to price this film so cheaply (I can’t speak for other Foma films and other formats). Honestly I’d rather see they make it a few cents more expensive and give us a few cm more length. It’s annoying to have to fear losing one’s first or last frame of every Foma film.
It almost seems that the more I mess around with this film for the wrong reasons, the more I get to like it. I love the tones. A bit like APX100 (which I never got to try in 120), but then maybe even nicer, because more grey-tones. I hope for Adox Pan 100 to come out soon.