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robert taylor
17-May-2011, 21:35
Hopefully some of you will have the definitive answer for this frustrating enigma: thin, usually long lines of high density appearing on 4x5 negatives, in this case 2013 exp. date Tmax 100 shuffle/tray developed in Tmax RS developer 1:9 (6 oz. fresh RS + 54 oz. water), 9 mins. at 75 degrees, same approximate temperature for water pre-bath, stop and rapid fix (for 6 minutes), number of sheets in batch developed was 8. Four of the 8 negatives showed this defect. In the affected negatives these very thin high density lines (3-6 or so of them depending on which negative) typically run horizontally/slightly diagonally 1/2 to 2/3 the length of the negative and are limited to the upper 25% of the negative (in this case, across sky/clouds). The lines are not perfectly straight or perfectly parallel to each other. A few of the lines are fairly short and some lines extend through the clear negative edge. I had this problem 5-6 months ago with Acros film developed in Xtol at 75 degrees (as I remember anyway). Also, some years ago the same defect appeared on a couple of 8x10 TriX negatives developed in HC110. On the other hand, none of the 4x5 TriX negatives developed in today's session in HC110 (N development, 68 degrees, same tray development plan) have the lines. Any help any of you may have in this regard will be greatly appreciated--to say I am frustrated by these results (destroying some of the best negatives from this trip) is vast understatement! Thank you in advance for your input.

Brian Ellis
18-May-2011, 04:53
Without seeing the negatives it's hard to say but from your description it sounds like a light leak of some sort, either in the camera itself or in the film holders. Anything I can think of related to the development process itself that caused lines of some sort would tend to produce the opposite of what you're getting, i.e. the lines wouldn't be dense they'd be thin because developer wouldn't have reached the areas in question.

Do you by chance sometimes pull the dark slide and leave the camera sitting in bright light for a while before making the exposures on the affected negatives? I did that when I first started using a large format camera and got lines in the negative similar to what you're describing. But that's just a guess, it would help a lot if you could post pictures of a couple of the negatives.

robert taylor
18-May-2011, 09:27
Hello Brian and thanks for your input. Hard to see in any image I could attach since they are very thin lines that even when seen on a 16x20 print would not immediately catch the eye (appearing on the print as VERY thin, well defined white lines typically running across 2/3 or so of the image). On a 4x5 negative they are only readily discernible on the light table with a 4x loupe when I am checking the negative for the occasional "dust speck" defects. To better visualize this on a 4x5 negative, imagine that some evil gremlin has magically imbedded within the emulsion several 3-4" long strands of thin human hair left to right and in approximate parallel across one of your "best" negatives immediately AFTER you have made the exposure. When you develop the negatives the evilly imbedded hairs have added density to the emulsion and print as almost white lines as thin as if you drew them across the print with a well sharpened "white-lead" pencil. You could even artfully spot-tone them out on the print with a very fine tip brush IF you had many hours to curse over having to do so. One could imagine that this defect might have occurred in the coating process at the factory but I don't think that to be the case...if it were I think I would see more Tmax negatives with the defect (even the other negative in the same holder may not have it). My hope is that someone out there bothering to read all of this may have had the same problem and have been smarter than I am about figuring it out. Otherwise, I may have to start to believe that I actually have been assigned some evil gremlin to "help" me atone for past transgressions. Sincere thanks again to you and to anyone who may be able to help solve this DEVIL of a problem!

Robert