Lateral Agitation?

[brian_y3]

<p>In general, what are your thoughts on lateral agitation? In particular, I mean agitation that involves moving the tank from side to side and/or in circles but never tilting or inverting it. Figure 8 agitation is one such technique, whereby the tank is moved vigorously along figure eights on or off the work surface. I'm having a problem with foam that seems to be alleviated only with lateral agitation. I've read it can cause problems with 35mm sprocket holes (I've only done it with some test strips of Acros in 120). And in general, I'm wondering how effective it is in delivering fresh developer where it needs to be. Thanks.</p>

[thirteenthumbs]

<p>Continuous rotary rotation works very well. There is no reason turning the tank a few turns for each agitation cycle will not work <strong>BUT</strong> the tank needs to be turned an equal number of turns in each direction to minimize/eliminate streaks from rotation. I rotate my 135/120 tank 2 turns at the end of each inversion cycle changing directions each cycle. I use constant rotary processing for4x5 sheet film changing direction every minute.<br>

I have no streaks or uneven development.</p>

<p>Less vigorous inversions should reduce or eliminate foaming or filling the tank to the top of the cap should eliminate it. A different developer may foam less. An air space is not necessary for good agitation.</p>

[glen_h]

<blockquote>

<p>An air space is not necessary for good agitation.</p>

</blockquote>

<p>I suppose not, but it helps.</p>

<p>For a stainless tank, there is room for a slight vertical motion of the reel, which it will do on inversion. It won't move very much for side to side motion. For rotation, there won't be much relative motion between the fluid and film.</p>

<p>Inversion with air space will force the bubble through the space between the film and force solution with it. For side to side motions, there will be some sloshing which will also help.</p>

<p>With no air space, you have to be more vigorous in tank motions for the same agitation effect.</p>

[PapaTango]

<p>Brian, do you 'bump' the bottom of your tank a couple times on a rubber mat a after agitation? This is a sure fire method to dislodge any air bubbles on the film, break up most of the foam, and dislodge any air pockets that might develop (pun intended) between the film in the reel.</p>

[chris_waller]

<p>My agitation regime is: 6 inversions in the first 30 seconds then 1 inversion every 30 seconds after that. If you are getting foaming then I suspect you are over-agitating.</p>

[brian_y3]

<p >Thanks. I tried to word my post so that it didn't go down the worn path of "which agitation is best." Suffice it to say my inversions are SLOW and GENTLE, and I rap the tank hard several times. I'm using the taller Paterson tank that hold two 120 reels. I believe inversion is best, and for other combinations of film and developer that I use, it's fine. But when it's not, I'm wondering if lateral agitation (in a tank not filled to capacity) is sufficient to move things around. </p>

[PapaTango]

<p>If you were using a rectangular tank such as a Yankee or HP Combi-Plan, then maybe so. But in a reel type system--especially a tall one that may contain multiple reels--not so much.</p>

<p>Going from side to side is not really enough to cycle and replenish the relatively thin layer of developer that is sandwiched between the film layers--unless you are relatively aggressive about sloshing the tank to and from From what I am gathering, that is not your chosen course...</p>

[bethe_fisher]

<p>All I can say is that my worst negatives as far as regular-ness were 4x5 ones I did in a combi-plan when I rocked it back and forth instead of inverting it. I did that batch that way because I had some sheets fall out of their grooves on the batch before. When I invert a tank, I do it deliberately. For 120, when I thunk my stainless tank on my stainless sink, it can be heard upstairs quite well. No airbell issues on my recent rolls (all chemistry and rinses done with Walmart distilled water). I know the foam you're dealing with and I don't have that, though. <br>

Is there any chance that the foam is from cleaning the beaker and tank? Maybe a lot of extra rinsing in very hot water would get any residues off? Want to try stainless and borrow mine?</p>

[thirteenthumbs]

<p>@ Bethe I had sheets fall out of their slots in a Combi Plan that I had. I assume its standard operating results when using that tank for inversion. </p>

<p>@all I have used my Jobo 2500 tank in an inversion session or two but prefer to use manual rotary processing due to the weight of the tank when full. Manual rotary is roughly 60 rpm reversing direction every minute. I start with fingertip and push to heel of one hand then repeat with the other; reverse direction is heel of hand to fingertip, steady pushes or pulls.</p>

<p>500ml stainless steel tank with either 2-135 reels or 1-120 reel invert for 1/2 second then return upright for the first 30 seconds then 5 to 10 inversions every 30 seconds throughout the rest of the processing time. I tap the bottom of the tank two times on the sink at the end of the inversion cycle then turn 2 turns without lifting the tank and changing directions each agitation cycle. Even development, no foam, full tank-no air space, consistent results with this technique over the years with Microdol X, FG7, Rodinol, Xtol, HC110; Agfa, Arista, Ilford, and Kodak films.</p>

[jose_angel]

<p>I use the Patersons with the provided small pipe for rotary agitation, usually four turns; one right- one left- one right -one left, with a gentle, non vigorous movement. I spend about ten seconds to do that.<br /> It has worked for me since I started film developing back in the seventies.</p>

[bethe_fisher]

<p>@Charles - I had developed at least 100 sheets in that Combi-Plan with no issues. Then the end pieces that have the slots got loose somehow. I'll be trying the Mod54 next, I think, but I've heard you have to agitate gently with that. I thought about the Jobo tank I have (no Jobo, just two tanks), but it won't work for inversion as it leaks too easily and needs so much chemistry for just 6 sheets unless you're doing it on a Jobo. <br>

Brian - good luck!</p>

[thirteenthumbs]

<p>I use Jobo's manual rotary base for rotary processing. Its hard to beat. If your Jobo tanks are leaking then you need new caps or lids.<br>

http://www.freestylephoto.biz/search?q=jobo or ebay.</p>

[PapaTango]

<p>I do not understand the problem some have with the Combi-Plan. I have developed many hundreds of 4x5 negatives--in places as simple as blacked out hotel bathroom tubs to my full darkroom. Approximately a hundred of these are permanently installed in the national LOC HABS collection. ALL OF THEM via inversion with no wandering of the negative.</p>

<p>Makes you wonder...</p>

[brian_y3]

<p>@Bethe - Thanks for the offer on the stainless tanks. I want to try a few more things. I should add it's only the top reel that has the problem with foam marks, and it's only the combination of Acros and HC-110. I like this combination and want to make it work, but I'd also like to do two films at a time and not one.</p>

[bethe_fisher]

<p>@Patrick - that had been my experience, too, then the one batch had several sheets fall out. It really seems like the rack suddenly became loose. It's also possible I didn't do my best job loading those because I was using a changing tent instead of a darkroom. Either way, I'll know soon as I plan to develop some more sheets in the next week or so. The messed up ones were not that long ago and I ended up sending several out in the meantime because I didn't have time due to a move.</p>

[thirteenthumbs]

<p>If the top and bottom parts of the sheet film holder in a Combi Plan are not rigid to the central support the film will fall out of the holder. Mine was loose fresh from the factory sealed box and it leaked. I bonded strips of plastic to the frame to make it rigid which ended the film falling out but I never could stop the drip from the drain spigot.</p>

<p>I sold it and moved on to Jobo, best move I made with regard to processing equipment.</p>