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  1. #21
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    Thank you all for your suggestions. Some contradicted others so I did my best guess of what to try first. Ideally I would make one change at a time, but there were simply too many, so I took a chance. Since my last post I developed the film in four holders and got significantly better results. By that I mean the edge density is still there, but much less in size and tone. Following are the things I tried. Please give me your thoughts as to how I can improve the process.

    Level tank: grhamp ….”make sure it is level and rotating on-axis.” The 2800 series tanks are two cylinders with a rib joining them together at midpoint. I made sure the water level of the Jobo was lowered so the tank rested on the rollers. The rollers hold the tank on axis. The 9” level I use for setting up the camera is perfect for testing this because it fits either side of the central rib. Good idea, but the tank was level and aligned, so no improvement here.

    Fill water at 68 degrees F, 20C. PE suggested this instead of the 70 degrees F I was using. Arbitrarily I increased development time from 6 minutes to 6:30. This later proved too long and I reduced it to 6:15 minutes.

    Sal Santamaura gave this link to his posting on new and old Jobo speed settings. http://www.apug.org/forums/viewpost.php?p=1610856
    Prior to reading his post I had been experimenting with reducing the speed from “4” to the first notch to the right of “F”. In doing so the problem became larger and darker. I returned to “4” and with these other changes things got better. Sandy King suggested reducing speed as far as possible, so I still have experiments to do there.

    Sandy wrote, “What I have found to be the Number 1, Number 2, and Number 3 solutions to this problem are, 1) weaker dilution and longer development time, and 2) slower rotation, and 3) lift the drum very early in development and rotate it up and down, and repeat this every two or three minutes.” I started by trying #3 every 3 minutes. After the first two batches with the speed set at “4” I tried two batches set a “3” speed and noticed an improvement.

    PE suggested a stop bath after development. Bostick & Sullivan’s instructions for Rollo Pyro say “At the end of development dump the solution and do two quick water rinses in a period of one minute.” I used water.

    keith schreiber suggested, “If your drum is a 2850, there is about 21 inches inside from end to end. If you are not already doing so, try positioning the film so that it is centered rather than inserted all the way.” I did try this. Unfortunately after the rotations Sandy suggested the film worked its way back to the bottom of the tank. Perhaps because the film was at midpoint for some part of the development this helped, but my first rotation was at one minute.

    Larry Gebhardt suggested, “You might try flipping the film around (notches to the bottom). That would let you see if it's a light leak in your camera.” I did this on every other sheet and found that the increase density was always on the bottom of the tank edge regardless of where the notches were. This was very helpful because I had gotten several suggestions that the problem was either in the film holders or the camera.

    In the original post I said, “I have ten film holders and the problem exists which ever film holder I use so I doubt it is a light leak.” I have since realized that I was only using four holders from one bag. This test batch of development was done with the same holders reloaded with the same type film, HP5+. There has been a significant improvement. Thank you all for your help. Based on this newer data what next steps would you suggest?

    John
    "If you want to be famous, you must do something more badly than anybody in the entire world." Miroslav Tichý

  2. #22

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    Reading that list, the common element seems to be that the edge nearest the base of the tank is being over developed. Since the axis is level, it has to be turbulence - locally more agitation at the tank base. It looks like you have one other test - film in the middle of the tank, and do not invert it. If the development is even with the film staying away from the base of the tank, there's the answer.
    I feel, therefore I photograph.

  3. #23

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    Quote Originally Posted by jp80874 View Post
    ...what next steps would you suggest?...
    Follow through on constructing an insert as discussed in this thread:



  4. #24
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    To catch you all up, here are my last two posts on the LF Forum. I’m doing this just so there will be a record of the problems and solutions found for the next guy encountering similar difficulties.

    3/17/14
    Sandy,

    Thank you. I tried the flashlight in the bellows. After about seven minutes I found the slightest sliver of light. There is a rectangular wooden stop for the film holder that is fastened in place by a screw at top and bottom. Both screws were loose after several years of knocking about. That eliminated about half the light.

    For the time being I have used a strip of gaffer tape to seal the crack. I will talk to Dick Phillips about a more appropriate fix. I am guessing remove the rectangular piece and add some padding. All that will show then will be an edge rather than the tape.

    I tried the fix with one of your holders and one from Lotus, the two brands I had been using when I discovered the problem. After ten minutes in the dark, no sliver of light. Thanks for taking the time to share your expertise.

    Next I will talk to Dana at Bostick & Sullivan about diluting Rollo Pyro and how much to increase the development time. There is still the question of why I got edge density on the notch side when it was turned to the bottom of the tank.

    Thank you.

    John


    4/19/14
    Now that winter and Cleveland’s grey skies are behind us I have been out shooting, developing and printing 7x17.

    “One of the suggestions was to center the 17” side of the film in the 22” tank so the film rested above the bottom of the tank. In my recent tests the film slid to the bottom of the tank during development, probably because I tried Sandy’s suggestion of rotating the tank.”

    The Jobo clips and the mesh bags that Jobo in Ann Arbor made do not seem to exist for 7x17. There are some for sale for 11x14 on eBay from Israel, but nothing for 7x17. The idea of trying to insert in those and then the tank in the dark is not really attractive to me.

    Several ideas of ways to hold the film off the bottom of the tank involved restraints that might have made their own turbulence. I had an idea that is simple, free and involves no modification to the tank or difficult loading. I cut two inches off the end of a failed 7x17 sheet of film (I had quite a few of those) and inserted it in the drum before the undeveloped sheet. In 12 developments of 2 sheets at a time, 8 times the 2”stips have stayed in place even after the rotations. When the strips have popped out during development, the 7x17 sheets have stayed in place, two inches off the bottom.

    The true test was printing. Each negative developed with the two inch strip in place has printed evenly, ie: without a lighter edge on the side of the negative near the bottom of the tank.

    I am really happy with this result and wanted to offer it to anyone suffering with the same problem. Thank you all for your suggestions and especially Sandy King for the detailed instructions.

    John
    "If you want to be famous, you must do something more badly than anybody in the entire world." Miroslav Tichý

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