More bubbles

Discussion in 'Black and White' started by gt|1, Aug 12, 2008.

  1. Ai ai ai, I've developed in Acufine and Rodinal in the past with no problems. Now that I'm trying XTOL I've had three rolls with bubbles along the edge. This last roll I definitely had the tank full, 500ml in a Jobo 1520, but the last two frames which were on the outer edge of the reel have bubbles along the edges (the tape end of a 120 roll is the beginning, right?). These are fairly new, clean Jobo plastic reels, 1520 tank, 120 film, I agitate moderately for the first 30 seconds, then 4 inversions every 30 seconds after that, tapping the tank on the counter, and this last roll was TriX shot at 320, 68ยบ F, 8:30 min. When I took the cap off to pour out the developer I could see the bubbles. I've never bothered checking for bubbles at the top of the developer before because I haven't had this problem, so I don't know if XTOL is more prone to bubbling during agitation than Acufine or Rodinal? Any tips for mitigating this? Also, a question I posted in another thread that no one has had a chance to respond to it: "I've been looking for a summary of what happens when: you dilute developer push film raise the developing temps lengthen the time agititate more/less as far as grain, contrast, accutance, density, etc., go. Does anyone have a nice page that summarizes these variables? Thanks."
    00QU8Y-63747584.jpg
     
  2. This is a crop from the top right of the image. I was also curious as to what the light marks on the right side above the fence could be caused by. They're not extensions of the lens flare, right?
     
  3. Some developers are more prone to foaming than others. It's the difference in surface tension due to differences in the chemical ingredients. I've experimented with several developers, opening the tank during tests, to see how they behave after agitation.

    While the subject of agitation produces occasional debates, in my experience based on these observations, plastic reels are more likely than stainless to produce foaming with inversion agitation. My theory is that the higher flanges and sharper shoulders of plastic reel guides produces more turbulence. After observing this several times I switched to twist paddle agitation only with plastic tanks/reels. That eliminated the foaming.

    If you prefer inversion agitation or must use it (I don't know whether twist paddle agitation is possible with the Jobo), be sure to fill the tank to the top to minimize airspace. This will effectively reduce the risk of foaming. Some folks will argue that some airspace is needed for adequate chemical flow. I haven't found this to be true. If in doubt, try a simple experiment: fill an ordinary household jar with water and add any ingredient, such as a bit of food coloring, oil, sugar, etc. See how much agitation is needed to distribute the ingredients. If your results are like mine, the standard inversion agitation that's appropriate for film development will be sufficient to distribute the test materials. If anything, the presence of the reel and film itself will aid in producing enough turbulence to assist in chemical flow.

    Also, plastic tanks tend to have more convoluted lid designs. Between the funnel and light baffle, they can actually trap some of the developer or fixer. So if you use only the absolute minimize needed to cover the reel, you may leave the upper edge of the film high and dry after some fluid is trapped in the lid. This is a definite problem with the Spanish made plastic tanks that used to be commonly available. Less so with the Patersons, but still a minor risk. Don't know about the Jobo, never used one.

    Finally, if you use the Ilford method for washing in the tank and use a drop of wetting agent to aid in spot-free drying, be sure to rinse the tank and reels in tap water afterward. There is a slight risk that residue from Photo Flo or other wetting agent can affect the surface tension of the next batch of developer and produce foaming. I've tested this and the risk is very minor and easily avoided by rinsing the tank/reels after use.
     
  4. BTW, those artifacts angling toward the upper right corner do appear to be flare. While the iris-shaped ghosting flare is obvious, some flare artifacts can be elongated or otherwise irregularly shaped. If you experiment with a high resolution scan digitally, adjusting the contrast, sharpening, etc., you can often isolate the shape and distribution of flare artifacts and ghosting to see the effects that might otherwise go unnoticed in a normal print.
     
  5. Thanks again for everything Lex. The Jobo tanks, at least the ones I have, don't have twist paddle agitation, and this last time I definitely had plenty of developer in the tank.

    I use a separate tank for photo flo after washing my film in an Aqua Vac film washer and I clean the reels pretty well.

    Based on that crop above, if I went a little less and gentler with my agitation, what would my results be?
     
  6. I'd suggest sticking with conventional inversion agitation. Instead of rapping the bottom of the tank to dislodge bubbles, which in my tests can actually *create* more bubbles, try the Uncle Frank*** trick: thump the sides and top of the tank by flicking it with the middle fingernail or thumbnail.

    ***A bit of history... when I was a kid growing up in Mount Vernon, NY, my babysitter, Jeannie, had a crazy brother named Frank, a rambunctious middle aged New York/Italian guy who was entertaining as hell. When we'd be in the swimming pool, Frank would do cannonballs right smack into our midst. He knew every almost but not quite dirty joke in the book. Had all the tricks - pulling coins out of ears, etc. He taught me to play poker and loaded my hand with a royal flush during my first game to make sure I'd win - I was watching him shuffle and still can't figure out how he did it. After that I never got another winning hand. One of his favorite stunts was to shake up a can of beer (always Schlitz) and pretend to open it in your face, causing us to scatter to dodge the foam. But just before opening the can he'd flick it with a fingernail, which broke up the bubbles ... no foam. Anyway, that's the history of the Uncle Frank fingernail flicking trick to dislodge bubbles. To this day I still pull this stunt on my own nieces and nephews.
     
  7. Hahahaha, nice story. I've never been too lucky with the fingernail flicking on beer cans but I will change my bubble reducing method by thumping the side or top of the tank next time.
     
  8. Greg,<br>
    With the Jobo tank you should pre wet the film. Fill the tank full of water the same temperature that you plan to develope at OR higher/ lower temperature water to bring the tank/reels/film to the developing temperature. Allow the water to sit for 30 seconds to 2 minutes. I normally fill the tank with water then mix the Xtol to the dilution I plan to use, dump the water then add the Xtol and start timing.<br>
    Pick up the manual roller base and do constant agation by continually rolling the tank during the developeing time. The roller base is adjustable to any Jobo tank. Be sure to rotate the tank the same amount of time in each direction for the duration of the development. I normally rotate turning the tank away from me for 30 seconds then turn it toward me for 30 seconds. I never have any uneven developing, air bubbles, or pin holes.<br>For my setup/processing I find the developing times for inversion -15% better than the published times for continous agation.
     
  9. These marks are definitely lens flare, not bubbles, FYI. Lex is right with his identification of the shape of the aperture
    iris; bubbles will almost never take that shape- they'd have to be packed together, honeycomb style to do that- very different from what
    we're seeing here. The other
    give-away is the straight line formation- these are reflections off all the air-to-glass surfaces on the lens.
     
  10. No, in addition to the flare there are bubbles at the top of the frame.
     
  11. The bubbles Greg refers to are clearly seen as dark blobs running horizontally along the upper edge. The distinctive iris shaped flare runs diagonally from the lower left corner toward the upper right corner.

    The mystery marks, which I also believe are due to flare, are the three light toned diagonal slashes just visible above the fence near the upper right corner.
     
  12. Follow up.

    I've been using Rodinal lately with zero bubbles issue.

    I'd like to also have a smooth grained developer on hand and am loving the convenience of Rodinal again. What's a liquid concentrate that will give similar results to XTOL?
     

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