Getting ready to do E6 processing with a Jobo expert drum...

[Steven Ruttenberg]

...and a kick starter rotary machine. From what I have read, rpm doesn't seem to matter much, but too me, if too fast won't work well. I was gonna start with 25 rpm reversing to process 10 sheets of 4x5 E100, Provia100F and Velvia100. I won't mix the film types though.

Should it be continuous or reversing or does it matter? Is 25 rpm too fast? I don't think so. Don't think it is too slow either given that till now I was using the Stearman Press SP-8x10 to process 4 sheets of 4x5 E100 where I did a decent first agitation by rocking the tray back and forth and then every 30 seconds did a 15 second slow rock of tray back and forth. So far the sheets look good.

This is why I settled on a reversing pattern at 25 rpm. Not too fast, not too slow, and imitates the rocking back and forth.

Thoughts? Gonna try this out tonight.

[angusparker]

You are braver than me. Let us know how it goes. I'm intimidated by the temperature control and toxic chemicals. But maybe I should have a second look....

[Steven Ruttenberg]

E6 is easy peasy so is C41. Just like black and white, but hotter.

[Vaughan]

Should it be continuous or reversing or does it matter? Is 25 rpm too fast? I don't think so. Don't think it is too slow either given that till now I was using the Stearman Press SP-8x10 to process 4 sheets of 4x5 E100 where I did a decent first agitation by rocking the tray back and forth and then every 30 seconds did a 15 second slow rock of tray back and forth. So far the sheets look good.

With tray processing the sheet is continuously submerged. With rotary the sheets are alternating between covered in the chemical and completely out. One of the hazards is uneven development due to standing waves forming in the liquid: regularly changing the rotation pattern prevents these, and reversing the direction is the simplest method.

If you look inside a well designed tank like the JOBO 2520, there are ridges inside that are unevenly spaced. These are there to break up the fluid flow and prevent patterns from forming, which would create uneven development.

[Steven Ruttenberg]

With tray processing the sheet is continuously submerged. With rotary the sheets are alternating between covered in the chemical and completely out. One of the hazards is uneven development due to standing waves forming in the liquid: regularly changing the rotation pattern prevents these, and reversing the direction is the simplest method.

If you look inside a well designed tank like the JOBO 2520, there are ridges inside that are unevenly spaced. These are there to break up the fluid flow and prevent patterns from forming, which would create uneven development.

Good to know. It will be nice to do 10 sheets of slide and color negative at a time. Even bw when not looking to do special development techniques.

[PatrickMarq]

E6 is easy peasy so is C41. Just like black and white, but hotter.

Indeed, for E6 just more products because I use the Bellini kit. Remember the first time my film came out: all milky white. But that seemed normal after drying wow.

[Steven Ruttenberg]

Processed the first 10 sheets of Provia100F. RPMs at 25, reversing. So far all looks okay. A couple of the skies "appear" to have a yellow tint to them, but they are also over-exposed it appears. Had this on a different slide when hand processing. Developed at 105F. The final rinse water ended up being warmer than 105, but doubt that would hurt anything.

Of note, when mixing the full volume of chemicals, I mixed the color developer at 2.75:1, water:color developer instead of 2.2. I don't think this would affect anything given how rough measurements are even using beakers like I do.

Question, if dilution for color developer is a bit more than should be, would increasing the time for color developer, like 15-30 seconds help? Or is it really needed to account for a slightly weaker mix?

To note: After practicing taking the lid on and off the 3010 expert drum, when it came to actually removing after developing, it was stuck tighter than a frogs a**. One method is to just keep working (would still be working it) another was to blow into the hole and a third was to buy the foot pump. I blew into the hole, took a lot of air pressure, when it popped it felt like getting punched in the mouth. I should have expected that being an engineer . Cut my upper lip a bit below my nose. Not bad.

I immediately went to BH and ordered the foot pump. Will be here Friday!

[Steven Ruttenberg]

And I like it. To develop 10 sheets of 4x5 in the amount of time to do 4, is excellent. Even for black and white when your not developing for a special method. Most of my images I try to make right in camera. I am starting to experiment with bleaching, using pyro again, push and pull processing, etc.`

[Tin Can]

Great story well told

I won't JOBO

However I have tiny quiet air compressor with 2 filters at 15 PSI, very controllable DRY air

In HVAC room

for dust and...

Processed the first 10 sheets of Provia100F. RPMs at 25, reversing. So far all looks okay. A couple of the skies "appear" to have a yellow tint to them, but they are also over-exposed it appears. Had this on a different slide when hand processing. Developed at 105F. The final rinse water ended up being warmer than 105, but doubt that would hurt anything.

Of note, when mixing the full volume of chemicals, I mixed the color developer at 2.75:1, water:color developer instead of 2.2. I don't think this would affect anything given how rough measurements are even using beakers like I do.

Question, if dilution for color developer is a bit more than should be, would increasing the time for color developer, like 15-30 seconds help? Or is it really needed to account for a slightly weaker mix?

To note: After practicing taking the lid on and off the 3010 expert drum, when it came to actually removing after developing, it was stuck tighter than a frogs a**. One method is to just keep working (would still be working it) another was to blow into the hole and a third was to buy the foot pump. I blew into the second hole, took a lot of air pressure, when it popped it felt like getting punched in the mouth. I should have expected that being an engineer . Cut my upper lip a bit below my nose. Not bad.

I immediately went to BH and ordered the foot pump. Will be here Friday!

[Steven Ruttenberg]

Great story well told

I won't JOBO

However I have tiny quiet air compressor with 2 filters at 15 PSI, very controllable DRY air

In HVAC room

for dust and...

I have a Rolair with separate storage tank. Very quiet. I have five filters on it and an ion air nozzle. If my house ever get's complete, I will have a dark room and my office both on separate Minisplits with no connection to the rest of the house's AC system completely isolating those rooms and keeping them positively pressurized, No dust getting in there.