Automatic agitation device / processor workflow and questions

[Mozg31337]

Hello everyone,

I have recently got hold of the B Processor (Dead Link Removed) for automatic rotation of the development tank . The idea is that I would like to minimise the time that I spend standing and babysitting the tank while the development, fixing, bleaching, washing takes place.

What I've noticed is that the processor only moves the tank in one direction, which seems a bit odd. The tank is positioned on the device under a slight angle though. I would have thought that you really need to have bi-directional agitation to make sure the chemicals move about in a more random way inside the tank. What are your thoughts on this?

Also, is there a need to change the time or amount of chemicals used when processing in an automatic agitation type device? If so, would someone point me in the right direction on how I can determine the changes that need to be made to the standard development process where you agitate the tank once every minute or 30 seconds?

Thanks

 

[AgX]

The oblique axle position seemingly was only done to assure simple attachments of tanks. Such of course lowers the fluid level at upper reel, which should be kept in mind.

Before changing anthing, process films that were as evenly exposed as possible, as on a lightable without lens. See if after processing anything non-homogeneous turns up.
If so, you could install a switch inverting polarisation that is triggered for instance by the rotating tank. Also an electronic solition is possible. Others might go into detail.

 

[Mozg31337]

Thanks for your reply, AgX. I have thought about the upper part of the tank being empty due to the almost horizontal position of the tank. But if the tank is going rotated, doesn't that rotate the reels and thus cover them evenly in a chemical solution anyway?

I am not an electronics guy, but I know someone who could take a look at the gadget and see if the rotation switching could be automated somehow.

But if anyone has tried and tested a similar solutions and have any feedback / suggestions / tips, it would be great.

Thanks

 

[AgX]

That the upper part of a rotating tank in horizontal stand is empty is normal. With Jobo tanks coupled to a filling processor (Lift) it even is necessary to be lower than the hub, for the tank not to run partially empty!
Also the volume of liquid in a rotating tank is much less than in an inverted tank, saving on chemicals.

With the tank in above machine though taking for example the volume given by Jobo for rotational processing, the level at upper reel would be lower than in a Jobo processsor. With the risk of the upper edge of film in upper reel no longer being wetted. ("upper" referring to the position in vertical stand)
Rotating in oblique stand is different from rotating in horizontal stand.