70mm 5 meter roll Tri-x development: HELP!!!!

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I am developing 70mm Tri-x on a stainless steel reel in a SS tank. All methods are preceded by 1 minute water soak. I've tried swirl development: 2 360 degree swirls every 45 seconds, reversing direction each time. I've tried traditional tank inversion, slowly, 1, 2 and 3 times every 30 seconds. Every method gets over developed film edges except 1 inversion, which gives uneven skies.

Any suggestions? Anybody use aprons?

-- andy buck (buckwiet@yahoo.com), September 24, 2000

Answers

Would you be so kind to include information on developer (inc. dilution) and your developing time. Also choosen filmspeed.

Regards,

Wolfram

-- Wolfram Kollig (kollig@ipfdd.de), September 24, 2000.


Sounds like the spirals of the reel are just too close together to get good circulation of the developer. You might try less developer in the tank, so that there's an increased air-space. That might improve the agitation.
Two inversions, once per minute, are usually all that's needed with most ss tanks and reels.

How bad is the unevenness in the skies?
If it's easily visible, and has fairly sharply defined edges, then it's likely that air pockets are getting trapped between the layers of the film. Another good indication that the spiral is just no d**ned use.

-- Pete Andrews (p.l.andrews@bham.ac.uk), September 25, 2000.


Thanks for the comments!

Pete: As I was writing it, I was thinking that 30 second agitation IS too much. I'll try two inversions at 1 minute intervals. However, it's been my experience that increased air/reduced developer increases agitation, i.e. developer movement, and makes the edge density problem even worse. As to your last comment, if not reels, then what?

Wolfram: TX at 50 to 100, Zonal-Pro (1-12) or D-76 (1-1) at 1/3 less than normal time. Yes: lower contrast negs, but wonderful midrange and shadow detail.

-- andy (buckwiet@yahoo.com), September 25, 2000.


Is this a single-reel tank or a two-reel tank?

-- John Hicks (jbh@magicnet.net), September 25, 2000.

Along with what has already been said, make sure your reels are ABSOLUTELY clean and free of Photoflo!!!

-- Scott Walton (scotlynn@shore.net), September 26, 2000.


The reasoning behind the increased air space is exactly as you say, it increases the agitation. However; when the tank is inverted, the air chases the developer out from between the layers of film more completely, so that when the tank is brought back right way up, then less-exhausted developer can flood back in. The result should be, not that the edges receive less development, but that the centre of the film receives more.
Agitation doesn't actually increase the developer's activity, it simply replaces exhausted developer with fresher stuff, allowing the proper rate of development to take place.

-- Pete Andrews (p.l.andrews@bham.ac.uk), September 26, 2000.

The problem is insufficient agitation.

Since you can't get a big air space in the inversion tank, I'd suggest you just run a tank line. Agitate by completely lifting the reel from the developer and plunging it back in, continuously for the first 30 seconds, then five seconds every 30 seconds or, probably more convenient, 10 seconds every minute.

Tupperware-style containers will be fine for this; no need for expensive stainless steel stuff.

-- John Hicks (jbh@magicnet.net), September 26, 2000.


Thanks for all the responses. I think it's interesting and funny that people feel I've been doing both too little AND too much agitation! However, I will try both remedies and report back in a week or two.

Andy

-- andy buck (buckwiet@yahoo.com), September 27, 2000.


Hello Andy,

thanks for the info. Using TX at 50-100 is a 2 to 3 stop pull, have you tried Gamma Plus at 1:20, also with shortened times? Sorry , but pulling is not my thing.

regards,

Wolfram

-- Wolfram Kollig (kollig@ipfdd.de), September 27, 2000.


Eh?
Nobody suggested you should give less agitation. What I was trying to say was, that 2 inversions per minute should be enough; provided the tank, reel, and amount of air space allow a sufficiently free flow of developer.
The amount that you shake the tank about has got very little to do with how efficiently stale developer is removed from the surface of the film and replaced with less oxidised developer. That's the point of agitation, it's not about giving the film a white-knuckle ride.

-- Pete Andrews (p.l.andrews@bham.ac.uk), September 28, 2000.


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