I'm leaving on a 4 to 5 week photographic trip and since I was low on my standard sheet films Tmax 100 and TRI-X, I decided that this is the time to switch films due to Kodak's bankruptcy and the uncertainty of future product availability. Since I have always liked HP5+ in roll film formats, I'm trying it in sheet film. I stocked up on 4x5" and 8x10" HP5+ and ran my Zone System testing. Years ago, I shot a small amount of HP5+ in sheet film formats and noticed that it seemed to be susceptible to pinholes but since I shot very little of it, I didn't know for sure if that was a fluke or a problem with the film but I did file a mental note to watch for it if I shot HP5+ sheet film in the future and I seem to remember reading a warning about this problem years ago somewhere. (I never had the problem with HP5+ roll film.) I use standard dilution stop bath (ascetic acid) and I'm guessing that that is the problem. It has never been a problem with any other film. Has anyone else had this problem with HP5+ sheet film and, if so, how did you deal with it? Did you dilute your stop bath or just use plain water. (I do like a acid stop bath for abrupt development stopping and to preserve fixer.) As a side note, one really sees how this film's E.I. responds to increased development times when testing it and why it has a reputation for being pushable!. In fact, for expanded development, the film is too fast for my taste and I will probably switch to a slower film but it's too late for that now. I'm leaving on my trip too soon to switch and start re-testing now. Anyway, if someone has dealt with pinholes with HP5+ sheet film, I would appreciate your comments.