Interesting discussion, which I would like to add a few comments and questions to. First, in defense of David's technique, I have also found that BPF scratches more easily than most other films during shuffling in the trays. Not only are the edges of the film rougher, but it seems to me that the emulsion is a bit softer as well when compared to T-Max, Tri-X or the Ilford films. Even the most skilled workers occasionally scratch a neg, and anything that will reduce that incidence would be helpful.
Also, I tray develop with PMK wearing vinyl gloves on both hands as mentioned above. Although a bit more fiddley than bare hands, it is remarkable how much sensation is retained and how easy it is to feel what you are doing. When developing large amounts of film, I simply leave the gloves on for the whole session, washing them like I would my hands and unloading the filmholders with them on as well.
Now on to my questions: I am curious as to the need for increasing development time when adding Photo-Flo to the developer. I would think that the surfactant would make it easier for the developer to break through the tension barrier and, therefore, increase it's activity somewhat. This would result in a shorter development time to reach the same density. Could someone clear this up for me if I am mistaken.
I am also curious as to why the Photo-Flo would cause the PMK to oxidize more rapidly than usual and turn so dark so quickly. Perhaps one of the photo chemists in the group could enlighten us. Possibly another type of surfactant would not have this effect.
Last, and most significantly, why would a surfactant, which breaks down the surface tension of liquids at a molecular level help to prevent scratches when developing. I would think that it would remove even the small cushioning and lubricating effect of the surface tension and make scratching negs easier. Could you explain your thinking on this to me? It seems I am missing something.
Thanks, ;^D)
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