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ageorge
18-Jan-2007, 11:24
I am processing 4x5 BW film in a Jobo 2521 drum by hand (i.e. no processor, rolling back and forth by hand) and I am concerned about my consistency with agitation and would really like something to automate the agitation. I don't have a darkroom and have to do daylight processing. What do others use? Is there a good motor driven rotator that works well? How many revolutions per minute are considered "normal" agitation? What other good options are there for daylight development?

Thanks in advance,
-alan

Nick_3536
18-Jan-2007, 12:27
The 2521 is too small for the various motorbases. You can either get an extension or the bigger 2551 tank. Then stick it on a unicolor or Beseler motorbase. Plug the base into a Gralab 300 timer and away you go. Motorized and timed -) Get a base that reverses direction if you can.

Jan Pedersen
18-Jan-2007, 19:28
Alan, there's a different thread about the same issue, you may want to read that.
I am pleased with the 2521 but as you can read in the other thread don't roll the 2521.

http://www.largeformatphotography.info/forum/showthread.php?t=22469

Christopher Perez
18-Jan-2007, 20:54
I just fill mine up with developer all the way to the top and agitate using the traditional film processing approach. Perfect negs every time.

Whenever I rolled either my Jobos or Unicolor drums parts of the negs were always "hotter" than others. So I stopped roll processing.

BradS
23-Jan-2007, 17:57
I just fill the kitchen sink with water at something close to 20 degrees C and float the tank in the water. It is real easy to spin when it's floating. Never any problem this way.

Before that, I used to use a little roller base contraption that I made using my kids' Legos. It worked great but my boys kept filching the parts and I got tired of rebuilding it every time I wanted to dev a few sheets.

Try the sink trick and don't worry so much.

Nick_3536
23-Jan-2007, 19:00
I used to do that with RA-4. How do you manage with the longer times needed for film? Would drive me nuts.

BradS
23-Jan-2007, 19:11
I used to do that with RA-4. How do you manage with the longer times needed for film? Would drive me nuts.

I don't know. Six to eight minutes doesn't seem that long to be bent over the sink with an arm in the water spining the tank...a little Tennessee sipping wiskey never hurts. Just be sure to keep it away from the beaker full of stop bath. :eek: