Need more help getting even lomo tank processing.

[aj]

That isn't too clever to use contaminated gear
But then, some use bucket processing in an attempt to get an interesting look by scratching and fouling the film.

Possibly you could attempt to get the substance of using a oil-solvent (which doesn't solve the emulsion or bearer).

[slashmaster]

That isn't too clever to use contaminated gear
But then, some use bucket processing in an attempt to get an interesting look by scratching and fouling the film.

Possibly you could attempt to get the substance of using a oil-solvent (which doesn't solve the emulsion or bearer).

Ya know, I really don't think it was because of the tiny trace of tranny fluid in the funnel. I think it was because of all the crusty chunks of buildup on the inside of the developer bottle which broke loose when I popped a dent out of the bottle. I've now watched the film and it is very unevenly processed even though I had agitated more than usual. Maybe I should have run the developer though a coffee filter to get those chunks out first? How long do you use your developer? I realize each film you do requires slightly more time than the last one. Do you ever have problems with chunky buildup on the side and bottom of the bottle breaking free?

[carllooper]

Thanks Carl! I know this camera normally gets very good registration for a non pin registered camera, especially at 8 fps. I think I set the driver to 1/4 microstep so it really jitters at 1 fps or less. I think that was my mistake Going to try it at 1/32 for my next film. Already turned the amperage and voltage as low as it goes.

To have the motor move slowly just move the motor by one step and then hold that position for however long you want to hold it, before going to the next step.

Don't use micro-steps because if the motor is trying to hold a micro-step position it can indeed vibrate (depending on the load it might be fighting). So, for example, if the microstep resolution of the controller is 32, then only use every 32nd micro-step position (counting the home position as zero) as a target position. That way the motor, upon reaching such a target position, will be at a position that is the most stable. Wait the required time (x milliseconds), and then move it to the next 32nd micro-step target position.

At micro-step positions (other than zero offset from an integer step), the rotor is trying to hold a micro-step position in between the integer steps of the stator, using different current proportions on the magnets either side of the rotor's micro-step position. Depending on motor torque and controller/software design this may not be as effective as one might otherwise wish, ie. causing some wobble/vibration at low rates.

So the workaround (other than getting a higher torque motor) is basically to have the motor go at a fast rate through all the micro-steps, before stopping it on discrete steps (every 32nd step, for a 1/32 microstep controller).

And whenever stopping don't stop at a position in which the claw is engaged with the film. Any instability in the motor will otherwise translate to claw instability and a corresponding instability in film position, ie. misregistration. But if the claw is otherwise retracted from the film then it doesn't matter if the claw is vibrating - as it's not being transferred to the film.

C

[slashmaster]

Thanks Carl!I plan to try that..