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stradibarrius
19-Aug-2012, 06:17
I have acquired a rotary tube film developer and am wondering what are the advantages of using a rotary tube?

Greg Davis
19-Aug-2012, 06:38
I use it for the low volume of chemicals necessary. Since I also process my own C-41, the temperature control of a Jobo is a nice convenience.

stradibarrius
19-Aug-2012, 06:49
I have searcher for instructions, specifically the amount of chemical required for 4x5 in an 8x10 drum. Suggestions on where I can find directions???

ic-racer
19-Aug-2012, 06:57
I have searcher for instructions, specifically the amount of chemical required for 4x5 in an 8x10 drum. Suggestions on where I can find directions???

It depends on what developer you are using; check the instructions with the developer. For example, if you are using T-max developer one-shot, using about 150ml per 80 square inches should give good results. If you are using Rodinal one part to 25 parts water, then 250ml per 80 square inches should give good results etc.
You don't need to know the minimum chemical volume to cover the film in your drum with B&W processing because in all cases that I am aware of, the minimum volume to cover the film in the drum is always less than the amount of chemistry needed to process the film.

sully75
19-Aug-2012, 07:20
They would be great but after using them for 5x7 for a couple of years, I finally had to give up on the 11x14 drums. Nothing I could do could make the film stay locked in place, no matter what drum I used (chromega, unicolor, bessler). Film always came loose and I would lose the one that came loose and the one it ended up hitting too.

I'm still doing two 5x7s in an 8x10 drum. Results are really good, but it's slow.

This has been worse with Arista.edu film than with HP5 for some reason.

I had pretty ok results with 4x5, less of a problem although I think I still lost a few.

JOBO 3010 is what I ended up with.

I use about 8oz of developer in an 8x10 drum, seems to work pretty well.

Paul

John Kasaian
19-Aug-2012, 07:44
1) use less chemicals
2) less handling (so less scratching)
3) takes up less room
4) except for loading the drum, the lights are on.
5) you can enjoy a cold beer while the processor does it's thing.
Whats not to like?
Check out Graywolf Phillip's Unicolor article on the LF Home page (click on the dark blue banner on the top of this page)

stradibarrius
19-Aug-2012, 09:09
Thanks for the info.

polyglot
19-Aug-2012, 19:33
If by rotary tube you mean "BTZS tubes" then you can trivially give different development time to each film while doing a bunch of tubes at the same time - just pull some of the tubes early and throw them in the stop bath with one hand while still agitating the other tubes. Means you don't need to sort your films into groups of N, N+1, etc and process them separately. Drawback there is that the manual agitation gets old real fast, especially for long developments.

I use a Jobo with 3010 so I can do 10 sheets at a time but they all get the same time. Nice to be able to walk away for 8-10 minutes while it processes, then again for fixing.

For BTZS tubes, you can fit only I think 60mL in each tube. For Jobo tanks, there are minimum quantities required to cover the film that you can google, e.g. 210mL for a 3010. If your sheets are on a carrier inside the rotary drum (like the Jobo 2509) then there will likewise be minimum quantities of chemistry to be respected so that they reach the inner sheets. If the sheets are on the periphery of the drum, then about 60mL is probably all you need - I think that's what Jobo quotes as the chemistry requirement for an 8x10 print and I tend to use 100mL for paranoia factor.

1 4x5 sheet is 1/4 of a "roll" (80 sq.in). Make sure you have enough active developer; e.g. 60mL of 1+50 Rodinal would be about 1.2mL which is not enough concentrate because you need 10mL/roll = 2.5mL/sheet.

Mark Sawyer
19-Aug-2012, 20:15
I have acquired a rotary tube film developer and am wondering what are the advantages of using a rotary tube?

I tried rotary tray processing once, but the developer kept falling out... :(

SMBooth
19-Aug-2012, 22:48
Your not spinning the tray fast enough

stradibarrius
20-Aug-2012, 04:59
My defination of Rotary Tube is from the tech sheets RE: processing. A rotary tube is a JOBO, Unicolor etc.

Brian Ellis
20-Aug-2012, 06:39
If by rotary tube you mean "BTZS tubes" then you can trivially give different development time to each film while doing a bunch of tubes at the same time - just pull some of the tubes early and throw them in the stop bath with one hand while still agitating the other tubes. Means you don't need to sort your films into groups of N, N+1, etc and process them separately. Drawback there is that the manual agitation gets old real fast, especially for long developments. . .

A minor quibble with this methodology for BTZS tubes (which I realize isn't what the OP is using but for the benefit perhaps of others who do use them) - when processing negatives for different times in the same run I found it easier to vary the times by starting them at different times and then removing them all at the same time rather than varying the time by removing them at different times. That way once they're in the water jacket you don't have to keep track of which tubes gets which time plus I thought I could get them into the stop bath faster when I was removing them all at once rather than removing some while continuing to agitate the others.

The 4x5 tubes hold 2 ounces of developer. I used D76 1-1 so I only had to use one ounce of developer per 4x5 sheet.

I didn't find manual agitation (which I did by just running my hand back and forth over the tops of the tubes as they bounced around in the water jacket) to be a pain but my times were typically in the 5 - 10 minute range. I can see that it might get old if you were doing longer times.

koh303
20-Aug-2012, 08:41
an royal ounce or an imperial ounce?

Why not use a globally recognized system that is the same everywhere...?

spacegoose
20-Aug-2012, 12:10
Not sure it was mentioned here, but one advantage might be less developing time - I believe it's recommended to reduce by 20% the times when using rotary processing.