I would like to develop some 4x5 and 8x10 b&w film in a Jobo tomorrow, and color film next week. This will be my first time doing it with a Jobo. If anybody has some hints and suggestions not mentioned in the manual I would appreciate it.
One question though, do you add chemicals while the drum is rotating?
What speed do you use?
Looking at the tubes the film slides into, it's amazing to me that the chemicals don't just sit in one tube. I guess they just slosh around evenly as the drum rotates.
If you're using a drum like the 3005/3010, look for Michael Gordon's recent post and link to his website, where he has an excellent video on developing LF in a Jobo. Even if using a 2500 drum, it would still offer some useful insights.
I take it you're using a CPP2 or a CPA2 with a Jobo Lift. (The Expert drums doesn't work with anything less than those processors anyhow.) You simply pour the chem's into the hole on the top of the Lift while the processor is running. It's also "common practice" to pour out the developer some 30 seconds before the end of the developing time (and at that exact time pour in the stop bath). The times for stop bath and fixer arn't that critical. Just see to that they are long enough.
Set the speed to the lowest setting "F".
Don't use any more chems than necessary, as the drum is quite heavy and puts a strain on the processor motor. It also seems like the consensus here is that you can set the processor to single direction rotation, as this will also save the motor. (There's a little "craw-foot" to the left of / in front of the motor axle which "clicks" back and forth. Just turn this e.g. 90 deg. so that the clicks doesn't engage.)
//Björn
PS/
The link to the excellent Michael Gordon video: http://michaelegordon.wordpress.com/...development-2/
I was busy today with three JOBO's going at once today.
Photo of film processing lab.
I have not noticed much of a difference (if any) between uni-directional and bi-directional processing. I believe that I will now make all of my JOBO's only turn in one-direction. If it saves the motors then I'm all for it.
I have two motors that I am going to have to have rebuilt. They were cannibalized out of the two units sitting on the floor under the left sink. Those are my two 'parts donors'.
Good luck with your JOBO processing. You will love it and how simple it really is.
One tip: DON'T use the lift to raise the tank. Raise the tank by supporting it with your hand from under the tank and also under the lift arm beneath the geared cogs. You WILL break the lift if you use the handle. I have removed all of the handles from my lifts so that my students don't have a choice.
Wow, that's quite the lab!!!Originally Posted by michael slade
Do you stop the rotation before lifting the drum? Some people insist that you should and some insist that you shouldn't.
Hehe> depends on if if the film is more important or the motor. Really makes no difference.
However you don't start the motor back up until the drum is down and in place.
I lift while the unit is rotating but turn off the motor before lowering the tank. Don't know why. Just my policy I guess.
Save the tanks! Save the gears! Turn off the rotation before you lift the drum! These parts are made out of plastic and are delicate. Please tell me that the last .5% of your development is crucial to the process...even E-6 isn't that finicky.
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