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Dark, brownish film after processing


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Hello everyone, I just hand-processed a roll of 16 mm in LOMO tank and the film is either all black or half-brownish, like on the picture. Visible frames are like underneath this brown strip. Is it possible that the tank leaks the light in? Wouldn't the film be clear in that case? Film is reversal FOMAPAN R, developed in FOMA kit.  

I am fairly new at this and probably asking something obvious?

Thank you for any advice,

Ivana

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I believe the brown part is undeveloped film.

You haven't managed to cover all the film with chemical- I would suspect insufficient solution or agitation. However you have black rebate opposite the perforations, which means that part of your processing was complete.

Also you have some damaged perforations so the camera needs checking.

Edited by Mark Dunn
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Oh thank you Mark. That's what I thought at first but in that case the film from the bottom level of the spiral should be fine, right? But it's almost all ruined, except about 30 cm that is completely fine – which is rather odd too because if there's a problem with chemistry or something (bleach maybe?), nothing should come out fine, I think. Also, it was all freshly opened and mixed. 

So I tried again, just a bit of film and plenty of chemistry, but the film came out completely black, even though I could see the image clearly during the 2nd exposure.

I just don't get it, I've used this kit before with Kodak super8 films and it came out beautifully.

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I haven't got the reversal process working correctly by myself yet but by my bad experiences, most of the problems seem to always be linked to the bleach stage one way or another when using the potassium permanganate based bleach. I have managed to get the emulsion completely fall off leaving only clear film behind and so on.(not the Foma bleach but a similar style diy mixed one). it just needs lots of testing to get it to work it seems....

I am intending to test Sodium Persulphate based bleach at some point. I have heard it is used in some processes and I have lots of that chemical because it is used for etching circuit boards

Edited by aapo lettinen
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Yeah most problems with B&W reversal come from the Bleach.

At Cinelab we don't use the potassium bleach we have developed a 'secret formula' over the years, the bleach tends to go flat likely from oxidation so you want to make sure you have fresh chemistry.

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Thank you, everyone, it seems that a bleach (potassium-based) was a problem indeed. I've been agitating lots more now. I've also noticed that the FOMA instructions on mixing are slightly different in English/Czech and German, so I tried the German version with reduced volume and tested several strips. It's so much better:

I've developed 5 test strips, first following the German mixing instructions and times, and then adding 15 seconds per test to every step because I also wanted to see if you can reuse the chemistry. It seems that black is a lot deeper when developing times are a bit longer, even the 2nd one. But then again, the 3rd one came out almost clear. It looked great during 2nd exposure, but suddenly that yellowish color went a bit darker, which was odd. Still, I've continued with 2nd developer and fixer anyway just to watch the emulsion wash away in the end. Can you over-expose the film during the re-exposure?

Then I did two more, all good. And the chemistry still works. Does it mean it would work in a large volume and with full-length film? I don't want to find out with serious material ?. I've read that developer can be tested on an exposed piece of film, is it possible to somehow verify if the bleach and clearing bath still work too?

Scan_test.jpg

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