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Thread: Uneven Development problem with semi-stand

  1. #1

    Join Date
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    Uneven Development problem with semi-stand

    I am new to LF and have been using BTZS tubes for about a year for developing my 4x5 TMax 100 negatives. I use 60 ml 1:1 diluted Xtol as this is what the BTZS cap can only hold. I agitate the tubes with a 2 cycle pinching technique. For a full 6 tube session, I pinch tubes 1+2, 3+4, 5+6, then side of water container + 1, 2+3, 4+5, 6 + side of container. This way each tube is rotated in opposite directions in a 2 cycle pinch. With this I found my EI is ASA 80 with density above Film Base + Fog of 0.11. My N developing time is 8 ˝ minutes at 75F.

    Equipment involved are Toho 4x5 camera, Pentax digital spotmeter and Nikon 210W lens, all purchased new. There should be no light leaks or other failures.

    Recently I got interested in stand development, adjacency effects and people’s glowing reports on 1:3 diluted Xtol. I also hoped to get some increase in film speed with this technique. The “open tubes in a can” method described by Sandy King previously would need to use a huge amount of Xtol. So I made my own tubes from grey 1.7 inch PVC piping. A 5.5 inch tube section (with cap at one end) can hold 220 ml. Just by pushing two of these tube sections together with a central connector, the tube complex is water tight. So it basically functions like a BTZS tube, except that the holding capacity is now 220 ml instead of only 60 ml in the original BTZS system. With 220 ml of fluid, the entire negative can be submerged and stand development is possible. 55 ml of Xtol diluted 1: 3 makes 220 ml, which should be adequate for 20 sq in. of film. I also found a plastic container which holds 6 of these tubes so I can agitate 6 tubes all at once by inversion.

    My agitation is slow inversion and up again, taking about 2+ seconds. I invert in 4 directions. I presoak for 1.5 minutes. Then, as described by Sandy previously, I agitate a full first minute, stand for the next minute and then start the “10 seconds in 4 directions inversion agitation” every two minutes. Empirically, I developed for 12 minutes (50% increase from my 8.5 minute N development time). That took five 10 second inversion cycles besides the initial full minute agitation. I then did the usual, stop bath, fix, rinse, hypo-clear, wash, photo-flo routine.

    With a new development technique I had to find my EI again. So I shot at ASA 64, 80, 100, 125 and 160 at a black board (Flocked light trap mat), placing it at Zone I. I checked the four corners as well as the centre for evenness. I also included an unexposed negative and that made 6 negatives.

    And now the results:

    Densities –
    Unexposed sheet – 0.01
    Shot at ASA 64 – 0.11 (0.10 above FB+F)
    Shot at ASA 80 – 0.10
    Shot at ASA 100 – 0.06
    Shot at ASA 125 – 0.06
    Shot at ASA 160 – 0.04

    So my EI using this development technique is ASA 64, a drop in speed instead of an increase.

    Even worse, the film shot at ASA 64 took on a “beaten silver” appearance, which I interpret to be uneven development. Here in my office, as far as I can recollect, the film shot at ASA 80 did not show the “beaten silver” appearance, or definitely less. The others shot at higher speeds did not show this unevenness presumably because the densities are less and so the unevenness if present was less noticeable. This did not happen when I worked with BTZS tubes.

    So where did I go wrong? I thought may be my tubes are the problem. So I bought a Jobo 2521 drum together with film loading facilities and did the experiment again with 1,300 ml of 1:3 Xtol.

    Densities –
    Unexposed film from last year – 0.02
    Shot at ASA 64 – 0.16
    Shot at ASA 80 – 0.11 (0.09 above FB+F)
    Shot at ASA 100 – 0.08
    Shot at ASA 125 – 0.05
    Shot at ASA 160 – 0.05

    Again the negative shot at ASA 64 clearly showed uneven densities as “beaten silver” appearance. The other negatives looked OK, though again the lesser densities may have made unevenness less noticeable.

    Can anyone help? Thanks.

    Greg

    www.gregoryngphotography.com

  2. #2

    Wink Re: Uneven Development problem with semi-stand

    What I read is not what I'd call "semi-stand" but words don't matter, results do.

    First, eliminate the presoak. I can't prove this but I think the well diluted developer doesn't "take up" well into the emulsion when the film has been pre-soaked.

    You do have enough stock developer per sheet at 55ml per sheet.

    If I understand correctly you have in each tube enough space for 220ml liquid and that much empty space in the cap above so that the developer can run to the other end of the tube. Is that correct? You need space for the developer to move. Change this if you don't have space for the developer to move.

    Next trial, just shoot one sheet of a completely even mid tone surface or clear even sky to get a totally even zone V or VI negative so you can easily see evenness or lack of. Exact exposure won't matter, 80 sounds fine. Just make something you can eyeball to see obvious evenness. Agitate that single tube with airspace above the film for the first minute then once each minute by simply turning it over and sitting it down once each minute until well done. (your time of 12 minutes seems in reason)

    What you describe (other than the pre-soak and assuming you do indeed have room for the developer to move) sounds pretty much like my standard procedure with roll film and Xtol 1:3 and pretty well the same mechanics as my sheet film in tanks. Its not semi-stand though, not by my definition. Try one sheet as in the preceeding paragraph and see what happens.

  3. #3

    Re: Uneven Development problem with semi-stand

    Your presoak time sounds short.

    FYI: I use a 1 minute tray presoak, then into tube. I use a presoak of 5 minutes. Fairly vigorous agitation for the first 1.5 minutes. Other agitation lift tube out 4 times and invert the last with total time of about 15 seconds - I'd call that moderately vigorous. I use pyrocat so I cannot comment on the developer.

  4. #4

    Join Date
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    Re: Uneven Development problem with semi-stand

    I use exactly the same time regimen you describe, with TMX in XTOL 1:3, in both a Combi Plan and a Jobo 3006. I use a 5 minute presoak. I can't say how crucial the presoak is though, because the couple of times I forgot to do it I could not detect any difference from my prior results.

    From your description I really can't see that you are doing anything incorrectly.

    By the way, my EI this way with TMX is 100.

  5. #5

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    Toronto
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    Re: Uneven Development problem with semi-stand

    Hi Greg,

    I recommend against inversion. I tried that (and 99 other methods) when I was teaching myself semi-stand and I couldn’t get even negatives.

    My method: I use a 16x20 development tray, which I fill 1 inch deep with water. After filling the tubes with diluted developer, I *gently* roll the tubes back and forth the length of the tray. For the initial minute of agitation the tubes make 5 return trips back and forth. Then I stand the tubes up in the tray. Every 3-4 minutes or so I gently lay them down again and roll back and forth for 2 return trips. The 1” of water in the tray acts as a lubricant and helps ensure a smooth roll. I also highly recommend a 1-2 minute presoak, inside the tubes.

    I've tested this method as follows: photograph a gray card or blank wall on zone 7, develop, scan into Photoshop and check evenness both visually and using the histogram (my standard deviation is 5 points or less).

    I also recommend trying HC-110 or pyrocat-HD, which are tested and reliable developers for semi-stand.

    You may also want to go with black ABS tubing instead of gray PVC. Some people have found the gray PVC not to be light tight.

    Keep experimenting and you'll get it.

    Mark
    Mark McCarvill
    The miracles of creative art lie not in particular materials and methods, but in the basic concepts involved. – Ansel Adams

  6. #6

    Join Date
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    Re: Uneven Development problem with semi-stand

    I wonder about your "gentle" agitation. When I first started using open tubes in a container, I gently rocked the container. I got uneven development. When I began using a closed tube for 8x10 and rolling the tube, my unevenness problem disappeared. When I returned to using the open tubes in a container for smaller formats, I covered the container and sloshed the tubes around vigorously and rolled the tubes in the container. I had no problem with unevenness. That leads me to conclude that you need to strongly agitate - just do it for a minimal amount of time.

    If you read the various discussions of minimal agitation developing, you'll see lots of variations. It takes a bit of experimenting to see what works best for you.
    juan

  7. #7

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    Re: Uneven Development problem with semi-stand

    Thanks all. THis will keep me occupied for some time.

    Greg

  8. #8

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    Re: Uneven Development problem with semi-stand

    I also found that I needed to agitate more forcefully to get even skies or white backdrops. I saw no noticeable impact on density and contrast when i did that.

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