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Jobo processing rollfilm-film end density creation

lensmagic

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When I develop rollfilm in the Jobo, the film end on the outside of the reel curls to contact or nearly contact the underlying film. When the film is agitated (rotated in the tank) the proximity of the film end to the underlying film creates an area of density on the underlying film. The density does not appear on the other (inner) end of the film. What can be done about this? My only idea at present is to cut an arc in the outer end of the film to allow free flow of the developer solution.
 

grahamp

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Put a reverse curl in the film end before you wind the last bit onto the reel. That should straighten it up. And make sure to wind the end of the film fully into the reel. If you leave the end in the loading cutout it will have more scope to curl.

I can't say I have ever noticed a problem like this. The film surface on the inside is going to be the backing, not the emulsion, if you load conventionally with the emulsion in, and that should not be sensitive to local flow differences in the outer layer. 1500 or 2500 reels, and what rotation speed?
 

ic-racer

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If you load the film with the emulsion side inward, the tail end of the roll can come close to next inner loop but the proximity is to the opposite side of the emulsion. If you already are loading it with the emulsion inward, realize that fixing affects the base side. Maybe this is where the issue is occuring. Can you post some pictures of the damaged film? Does re-fixing the damaged portion make the issue go away?
 

Sirius Glass

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Move the film further on to the reel.