Agitation, Tray vs Jobo

[don_wallace1]

I have just started using Jobo (an older CPE-2) for 4x5. That page of

Ansel Adams' "The Negative" which describes the problems of continuous

agitation keeps staring at me. You know, the one of the mountain where

he shows that continuous agitation increases the contrast too much.

But, of course, rotary agitation is continuous. And, I think, it

really reduces the development time. For HP-5 in HC-110, dilution B,

my time was just over 4 minutes. I read that under 5 minutes is too

short for a rotary processor so I went to dilution D (1:39 from

concentrate).

 

So what about it? Was Adams wrong? Is continuous agitation just fine?

 

Don Wallace

[daniel_jolicoeur]

Adams may have made alot of money writing books and selling photos, but if it works for you why wouldn't it be fine? Are you not happier using this technique? Why does every one get caught up in these paridyms "Adam's says" If it works for you use it.

[don_wallace1]

Daniel, I hear what you are saying but i assume Adams made that recommendation because there are consequences with continuous agitation (e.g., I have also heard of increased graininess). I quote him merely as an example of someone with experience. So my question was intended to tap the knowledge of others and find out about their experiences of continuous agitation in a rotary processor, hopefully to save myself from potential problems.

[william_marderness1]

I would not use HC-110 in a Jobo because HC-110 is a fast developer, so your times will be too short, or you will have to dilute it too much, which means there may not be enough developer for the amount of film. Try D-76 1:1.

[brian_c._miller]

Since continuous agitation increases contrast, lower contrast in another way. I use Xtol 1:1 or 1:2, which of course lowers contrast. Or print with a different grade of paper. Or preflash the negative before exposure. And on and on.

 

If you got a good negative for dilution B at 4 minutes, I wouldn't worry about it myself.

 

Basically, adjust your techniques for what you want to get, and run tests to make sure.

[jose_angel]

The rotary processor let me to obtain consistant results. I find that a compensating development are nearly impossible with this processors, but it's worth to me because this consistancy. This continuous agitation gives a much shorter dev. times (the high density areas goes up so fast).

 

I have been using TMX with Xtol 1:1, but the film speed is too slow; the results are good, but this low speed (if I'm not wrong, over 32ASA for a N-1 development ) makes it uselees in a lot of situations.

 

Now I'm using 400TMX with D76 1+1 @21 degrees C, and the results are muuuuch better, from N-2 to N+1. I use 300ml. of fresh solution each time. Five minutes of pre-soak. I keep the stock solution only for 3 weeks. Ask me for the dev. times if you need it.

 

I am not worried about short dev. times, near 5 minutes the results are good. Under five minutes with intermitent agitation the results could be not satisfactory, but with continuous agitation is different. Anyway, my N-2 is 5'15" at 160 ASA.

 

Hope this helps,

[gene m]

Constant agitation reduces perceived "sharpness."

[john_cook1]

Rotary processing is the brilliant solution to the problem of accurate color chemistry replenishment, which is nearly impossible for low-volume labs. It's not always such a hot idea for black and white chemistry.

 

Most (but not all) black and white film developers benefit from a lot of stillness, with very quick infrequent agitation only to disperse developer by-products. The constant motion of rotary processors prevents edge-effects, compensation and can introduce plus density areas from developer flow paths. In addition, the limited tube volume can preclude extreme developer dilutions.

[michael erlich]

Isn't tray development a continuous agitation technique? How do you get

compensating development in a tray?

[john_cook1]

Michael, as long as the film is submersed in the developer in the tray, it doesn't have to be constantly moving. This is called "still" or "stand" development.

 

Since only a portion of the material in a rotary drum is submersed, it must be in constant motion.

[john_hicks___]

Here's my opinion, fwiw...

 

http://unblinkingeye.com/Articles/Rotary/rotary.html

[c_p_goerz]

Maybe Ansel never used a Jobo in his 'constant agitation' tests,

did he ever say exactly how he developed that neg? I thought he

developed it in a tray with constant agitation and thats what gave

the overly contrasty look.

 

 

I have used tray AND Jobo for years and I LOVE that damn

machine!! I use PMK so it doesn't work for the larger sizes like

8x10 since the developer can splash onto a sheet (Expert

drums-I'm no cheapskate for my film!!)and give little specks, it

doesn't happen all the time but enough to pi$$ me of. Before you

post anything I did use a presoak and EDTA, nothing helped.

 

Now this is where it gets interesting, a year or so before I finally

bought the Jobo John Sextant did a film development article in

the magazine called Darkroom Techniques, in it he had

developed of film exposed to zone VI or so of a grey card-it was

evenly lit etc. He developed the film in a tray, a Yankee tank, Jobo

and with some contraption he had been cobbling around with. At

the end of the development test the negs were contact

printed..guess which one was the most even...?.... Yes! The

Jobo! It was TOTALLY perfect! I rushed out later and bought one

and I never had such beautiful skies...I had arrived!!!

 

 

Tray development is a pain when compared with the Jobo, you

sit in the dark and how that time drags as you slop the sheet

over and over in a tray hoping not to scratch anything, uugh!

There is no way around it for 8x20 etc so I'm stuck and will shut

up about it.

 

 

Now to the agitation, I have developed film for less than 5 mins

but I don't really like to, I never did have any problems but you do

get that little nagging voice in the back of your head. I used PMK

at 70 degrees for 7 mins with FP4 it came out great-60RPM by

the way. A film speed boost was provided by adding 1/8th TSP of

Amidol to the working solution prior to tossing it down the throat

of the Jobo. I ALWAYS filled the drum with nitrogen and

displaced the presoak water, this gives a cleaner base to the

film and less fog to print through. The developer comes out like

an iced tea shade as opposed to a heavily oxidized guinness.

 

 

If you do use HC110 etc then switch to a lower dilution and/or

mess with the temperature a little. For 'compensating effects' I

overexpose the film by a stop and pull it out the soup a couple of

mins earlier, I find that more controlable than than working it

from the chemistry angle. If you let the film sit in the Jobo forever

it will get contrasty but thats true of tray development too. With

tray development you also run the risk of uneven

development/scratching, and inconsistent results from the

developer heating up from your fingers or cooling down because

of the ambient room/counter temp. The Jobo has a constantly

maintained water jacket thats within 1/10th degree or less and

that keeps the developer/stop/fix and wash water all at the same

temp as well as the film and developer inside the tank itself. Its

very consistent whether Summer or Winter....I just realized I'm

writing an ad for Jobo and they aren't paying me so I'll end right

now!

 

CP Goerz.

[ken_schroeder]

Don, I recommend you purchase a copy of The Film Developing Book by Anchell and Troop. It discusses agitation, and is a valuable and practical reference book. HC110 may well not be a good choice with the Jobo. However, I don't think you went far enough with the dilution. 1:39 isn't much different than 1:31. I suggest trying at least 1:64. If you cannot add that much more water you may have to develop fewer sheets at one time. With motor driven 35mm that might be a problem. With large format, quality rather than time should be of the essence.

 

Anchell and Troop suggest using more dilute developer in the Jobo to compensate for the effects of continuous agitation. (p34) While that may lessen the problem, I think a better approach would be to consider a method which uses intermittent agitation. Have you tried tray development?

[jeffrey_scott]

I have use the Jobo 3010 drum for years and it works beautifully with very even development.

[george losse]

I've been using the Jobo tanks for a long time with HC-110 and have had no problems with the combination. I do process my negative to be contact printed so I like that HC-110 is an active developer.

 

Last year I broke down and bought a CPA-2 to process the film. I use the slower settings to process the film. Sometimes I'll speed the rotation up to gain a little more contrast. If I know the images need that. Most of the time it run very slow.

 

I don't mix the HC-100 straight from the syrup either. I mix the stock solution as Kodak instructs and then mix down to the working strength just before I process film.

 

I'm not sure the Jobo processors were around when the "Negative" was first writen.

 

George Losse