Doremus Scudder
Member
After looking at the negatives, I can see the increased density on one side (the top of the tank, I'm assuming) and some mottling/streaking. I don't really see any evidence of a light leak. If there were on on your Yashicamat, it would originate from a side; your streaking seems to begin and end inside the frame, hence I'm thinking it is a developing artifact.
For me, this all points to agitation; insufficient initial agitation (mottling/streaking) and agitation that causes a bit of surge along one side, developing it more than the rest of the film (increased density). I'm beginning to think that twirling may not be a good method; I've always used inversion and the famed "torus" motion for all my roll films. 120 film seems to be more susceptible to agitation defects. I'd try varying your agitation motion (less regular, torus one way and then the other, etc.), maybe try a bit less developer (550ml?) and make sure initial agitation is long and vigorous enough. Try a complete 30 seconds if you aren't already and use inversion. A water pre-soak may help as well (I always used one). With the pre-soak, the timing of pouring in the developer is not quite as critical. I had Nikor tanks, and filled them in less than 10 seconds. If you can do that, then you can put on the lid tightly and use inversion agitation. I know how frustrating this can be... keep at it and you'll find a combination that works for you.
Best,
Doremus
For me, this all points to agitation; insufficient initial agitation (mottling/streaking) and agitation that causes a bit of surge along one side, developing it more than the rest of the film (increased density). I'm beginning to think that twirling may not be a good method; I've always used inversion and the famed "torus" motion for all my roll films. 120 film seems to be more susceptible to agitation defects. I'd try varying your agitation motion (less regular, torus one way and then the other, etc.), maybe try a bit less developer (550ml?) and make sure initial agitation is long and vigorous enough. Try a complete 30 seconds if you aren't already and use inversion. A water pre-soak may help as well (I always used one). With the pre-soak, the timing of pouring in the developer is not quite as critical. I had Nikor tanks, and filled them in less than 10 seconds. If you can do that, then you can put on the lid tightly and use inversion agitation. I know how frustrating this can be... keep at it and you'll find a combination that works for you.
Best,
Doremus


