I have been experimenting with Efke IR820. So far I have only exposed one roll of Aura and one roll of non-Aura, both 35mm. The Aura was great, but the non-Aura had hundreds of very tiny black specks on the negatives (tiny white spots on the print).
I treated both identically. Exposed the same and developed the same (Xtol 1:1 for 14 min.) No presoak for either one. Water rinse after developer (no acid stop) and fixed in Ilford Hypam.
I have done a web search on this topic, but never came across a definitive explanation, although a number of people have apparently experienced these specks.
I was just wondering if anyone is familiar with this problem and knows whether it's ever been determined what the cause is. My suspicion is that, since the antihalation layer is the only difference between the two films, the problem has to relate to that. That makes me think that my not doing a presoak may be the root cause. I don't have another roll of the non-Aura film to try, otherwise I would just try it and see. Is it possible that the antihalation layer is getting embedded in the emulsion?
Another thing I noticed was that the non-Aura film seems to be significantly slower than the the Aura, presumably also due to the antihaltion layer. Somewhere I read (maybe in the data sheet) that the presoak enhances the film speed, but the data sheet doesn't differentiate between the two films when it discusses exposure.
I treated both identically. Exposed the same and developed the same (Xtol 1:1 for 14 min.) No presoak for either one. Water rinse after developer (no acid stop) and fixed in Ilford Hypam.
I have done a web search on this topic, but never came across a definitive explanation, although a number of people have apparently experienced these specks.
I was just wondering if anyone is familiar with this problem and knows whether it's ever been determined what the cause is. My suspicion is that, since the antihalation layer is the only difference between the two films, the problem has to relate to that. That makes me think that my not doing a presoak may be the root cause. I don't have another roll of the non-Aura film to try, otherwise I would just try it and see. Is it possible that the antihalation layer is getting embedded in the emulsion?
Another thing I noticed was that the non-Aura film seems to be significantly slower than the the Aura, presumably also due to the antihaltion layer. Somewhere I read (maybe in the data sheet) that the presoak enhances the film speed, but the data sheet doesn't differentiate between the two films when it discusses exposure.
.
