Is there any online source for reversal bleach and clearing baths on their own, especially permanganate bleach? I know they are available in the various reversal kits such as Bellini's, but I can't find anywhere that sells these two as standalone products. When I tried making my own the results were hit and miss.
Its really easy to mix yourself though. Chemicals are also not that difficult to find. You only need very small quantities of permanganate.
I have used it on photopaper, and it works well but goes bad after minutes so I use it one-shot only. Time and temperature is supposedly important when using it on film.
In additition to dichromate and permanganate, there is also copper-bleach and peroxide-bleach that supposedly works with reversal, but I havent tried those last two.
Permanganate and Sulfuric acid both can be regulated/restricted products.
Nonetheless, all you need is a tiny quantity of Permanganate to make Bleach part A and small amount of sulfuric acid to make Bleach part B.
You combine both parts only right before bleaching and it's a one-shot bleach, you discard it after use.
Is there any online source for reversal bleach and clearing baths on their own, especially permanganate bleach? I know they are available in the various reversal kits such as Bellini's, but I can't find anywhere that sells these two as standalone products. When I tried making my own the results were hit and miss.
No, there are no ready-made bleach part A and B available separately for hobby works.
Except for maybe Kodak which not long ago still was selling lab quantity of their reversal b&w process chemistry.
Is there any online source for reversal bleach and clearing baths on their own, especially permanganate bleach? I know they are available in the various reversal kits such as Bellini's, but I can't find anywhere that sells these two as standalone products. When I tried making my own the results were hit and miss.
The film fails to bleach properly. It looks sort of milky during re-exposure and after second development it's very dark, with some patches that seem not to have reversed at all. Disastrous, in other words.
I mixed it immediately before pouring it into the tank. It's possible that I didn't mix the chemicals properly, or maybe I should have used purified/distilled water instead of tap water. I might try that since it appears I can't get it as a manufactured product. I should be able to get battery acid locally and that might work better than dissolving sodium bisulfate in water as I had been doing.
It's mainly Fomapan R100 I want to develop. I think another option might be to do a test strip in the bleach immediately before using it on the intended film.
The film fails to bleach properly. It looks sort of milky during re-exposure and after second development it's very dark, with some patches that seem not to have reversed at all. Disastrous, in other words.
I mixed it immediately before pouring it into the tank. It's possible that I didn't mix the chemicals properly, or maybe I should have used purified/distilled water instead of tap water. I might try that since it appears I can't get it as a manufactured product. I should be able to get battery acid locally and that might work better than dissolving sodium bisulfate in water as I had been doing.
It's mainly Fomapan R100 I want to develop. I think another option might be to do a test strip in the bleach immediately before using it on the intended film.
I'd look into the sulfuric acid purity. You have to make everything in your power to eliminate all sorts of halogen (chlorine) sources along the way, including: chlorinated tap water, sulfuric acid purity, bisulfate purity etc... Use only lab grade permanganate (yeah I know it can be expensive) and lab grade sulfuric acid or bisulfate. Plus if you add 20gr per litre of hexameabiphosphate it can help too reduce the manganese oxid deposit after the bleach phase and will mantain the bleach mixed for a long time.
Have a look a the colour of the permanganate bleach just before using it. Is it cloudy? Is it towards a coppery red-purple instead of a clear vibrant purple?
Agitate all the time the bleach and Fomapan 100 R needs a longer bleaching because it has a silver anti-halo layer embedded in the emulsion that has to be removed by bleach action...