Diafine air agitation?

[discpad]

I'm building a small "bulletproof" processing rig for my ladyfriend, for

her to develop her own 120 B&W films. Basically, to make this as foolproof

as possible, I'm building it with four 3" ABS tubes 34 inches long, with

caps, all mounted on a small board, with hangers so the weighted film

strips can be dipped right in, yada yada yada...

 

To keep this simple, **and since she's in midtown Manhattan with plenty of

film stores** I'm setting her up with Diafine, as the one gallon kit

should be just right: bath A, bath B, fixer, wash.

 

My question: Agitation. I know I can use a sparger (Ron's 50 cent word for

aquarium stone!) and air pump to air agitate the fixer. However, what

should I do for agitation for Bath A and Bath B? Or, for Bath B, should I

just leave it as "stand" development?

[discpad]

By the way, when I'm done, I'll post a picture of the contraption right here! :)

[jay_de_fehr]

Dan,

 

no offense, but your "contraption" seems like a solution in search of a problem, unless your ladyfriend is handicapped in some way that leaves her unable to load a spiral reel.

 

Jay

[discpad]

She has trouble loading even her Mamiya 645AFd!

[michaelging]

well you can't use air for agitation on the developer as it will add oxygen and kill the developer. They used to use gas to agitate film ,but I believe it was a inert gas, like nitrogen.Maybe you could use a vibrator,to give constant agitation,or a blender in the dark.:)

[discpad]

Michael,

 

Notice carefully that I said Diafine, which is a 2 bath developer. I can see air causing problems in the 2nd bath; but not the first bath.

 

By the way, I also process E6 and C41 in my Jobo ATL-3; and I've also used a Refrema E6 dip & dunk, with nitrogen burst agitation in the first & color devs; and air agitation in the bleach & fix.

[lex_jenkins]

Agitation of Part B must be done very careful. It's better to err on the side of agitating too little than too much. I usually agitate very gently about once a minute.

 

With constant bubbling there's a risk that the Part A in the emulsion could be dislodged before it has a chance to interact with Part B. Same as too much agitation.

 

I'm inclined to agree that it's a clever solution in search of a problem. I'd save it for use with ordinary one-shot developers. I doubt that 10 minutes of air bubbles would kill most developers, especially since one-shot developers will be dumped.

[discpad]

Lex, normally I would recommend single-shot developers for a reel-and-drum configuration, such as D76 1:1 (though I now use D76 & D76R in a replenished line in my Jobo ATL-3); the problem is that the 3" diameter ABS tubes will be ~36" long (~90 cm) for a volume of about 4 liters -- That's a LOT of developer to toss out!

 

Also, I'm trying to make this as fool-proof and painless as possible, as I'm trying to get Lisa to shoot more 120 film without the constant pain of huge bills from Duggal. For this duty, Diafine seems like the ticket, since it works between 70 & 80F, and

 

Now, all I need to do is convince her to shoot her film with the EI settings printed on the box of Diafine, not the ISO number on the film wrapper! :)

[discpad]

<p>

Please click on the new thread titled <a href = "http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00F6pF&tag="><b>Inexpensive two bath developers <i>besides</i> Diafine?</b></a> to continue this discussion, since I changed the question.

</p>

[scott_walton2]

Dan, reading your whole thread...1- don't plan on using air for agitation (for two reasons 1- is that air will degrade the developer and 2- there is a thing called a plenum in the bottom of large tanks that is used to spread nitrogen evenly. Plenums aren't just a simple row of tubes hooked together, yes it does look like that, in the shape and size of the bottom of the tank but they also have varied sized holes for the nitrogen to flow evenly... small pinholes closest to the intake manifold going to slightly larger holes at the far end of the plenum. This way, the nitrogen flows evenly and is distributed evenly across the base of the tank (a little math goes into making and adjusting them) and just by using a simple tube, you run a great risk of uneven development due to the uneven agitation and scratching the film.

Also, Diafine is a great developer but with the testing I have done, you will not have as much speed gain as you do souping 35mm. Testing should be done to find the optimum ASA as with any new process.

[discpad]

Scott,

 

First off, thank you for looking at both threads.

 

Now, on to the air agitation: I'll be using 3" diameter by 36" long ABS tubes in a line, for a truly foolproof dip & dunk line! The agitation would be with a 3" aquarium stone at the bottom, which, in my experience agitating my 5 gallon E6 bleach tank, does a surprisingly good job producing lots of baby bubbles.

 

[by the way, I've worked on a big Refrema E6 dip & dunk, so I know what you're talking about with the aeration tube assemblies.]

 

Now, on to what you've observed with Diafine: What do you see for shooting ISO's for 120 vs 35mm -- On the order of 1/3rd to 1/2 stop?

 

Thanks again!

Dan

[bill_napper]

Sounds like an interesting idea. Could you somehow make both ends "waterproof" and just invert the whole thing once a minute? If you mounted it balanced it would just take a flip and it would invert. Since timing is no real issue with diafine just make it a two or three barrel unit, load three rolls and go!

 

If not put a small rod in thru the top with a cam type arrangement. Turn it ever 30 seconds or so. Hang the film from the rod.

 

It would take three gallons of diafine to fill all the tubes but the stuff last forever! The batch I am using now was mixed in early 2004!

 

Just my $0.02.

[lex_jenkins]

As I think about this problem a couple of possible solutions occur to me. The main problem seems to be the awkwardness of handling developing tanks that are nearly three feet long.

 

1. Use a camming mechanism with a mated spindle, as with the Paterson and Spanish made plastic tanks. Use twist agitation.

 

2. Instead of a camming mechanism, use a lift-and-drop technique. Leave enough overhead at the top of the tank to accomodate at least two or three inches of vertical movement.

 

3. Instead of pouring out Parts A and B, build a drain into the bottom of the tank. Altho' timing isn't critical with Diafine it would probably be a good idea to use a high flow drain.

 

4. Instead of draining the tank, use two tanks. One holds Part A, the other Part B. When finished with Part A, turn off the lights and transfer the film on the reels and spindle from the Part A tank to the Part B tank. Continue processing.

 

As I think of it, using Diafine for large scale processing with large tanks might best be done with four tanks, one each for Parts A and B, one for stop bath or water, one for fixer. The developer and fixer could be left in the tanks for long periods since they're reusable. The water could be replaced after each session.

 

To facilitate doing the entire process in the dark, up until fixing, the tanks should be secured to some sort of base at the bottom to eliminate the risk of knocking over the tanks in the dark.

 

Just a thought, but this seems like an efficient way to run such an operation.

[discpad]

Lex, great minds think alike! :)

 

Actually, it's exactly what I'm building, with five 38" long 3" ABS pipe tubes, with them sealed at the bottom with knock-out plugs mounted to a board, and 1/2 inch wood trim spacers between the tubes (to allow room for the caps).

 

These tubes have collars inside, which I made by taking a 2" long piece of this pipe and cutting out a strip, then bending them to fit inside. These collars have two rounded notches in them, like an ashtray, where a 3" long x 3/16 dia. dowel drops in. Attached to each dowel is a film clip, and I'm also providing her with weighted clips for the other end of the film strip.

 

Four of the five tanks has a drain fitting at the bottom with a nipple, and a 6" stub of tubing and a clamp. The wash tank has fittings at the top and bottom, with a drain hose at the top and the inlet hose at the bottom. I'll be installing an icemaker saddle tap on the cold water line below her bathroom sink, connected to a short (2-4") piece of tubing and an inline shut-off valve, which connects into a 10' piece of tubing, stored in a coil below the sink. She'll plug it on to the nipple at the bottom of the rinse tank when she needs to use it, and then take another piece of hose from the nipple at the top to the sink or bathtub.

 

The reason I made the tubes 38" long is so that, if I can get my hands on double weighted clips, she can also process 24 & even 36 exposure 35mm, as well as 220 film. But, I'll also have to make some sort of hanger bracket, so she can easily load them in the dark.

 

I'll post pictures when I'm done!

[lex_jenkins]

Cool! Looking forward to seeing the pix.

[mrbob]

Why go to all this trouble? Gustavo Gonzales takes about a half hour to teach college students at The City College of New York and the Fashion Institute of Technology how to load 120 and 35mm stainless steel reels foolproofly. Part of the secret is to use Hewes reels, which are made of heavier gauge stuff than any you can buy these days and which have clever catches at the reel hub for securing the film and getting it centered. Hewes reels are about the only things Calumet sells cheaper then B&H or Adorama.

 

BTW air bubbling would not be a good idea for any single solution developer. Diafine and homebrew divided developers work by keeping the developing agent and preservative in solution A. After the emulsion imbibes all the liquid it can hold (over the course of 3 minutes or so), A is poured off, and B is poured in. B cotains the activator i.e. an alkaline solution which triggers the developing agent (now residing in the emusion) to start developing, a process which also takes about 3 minutes. The film cannot be overdeveloped because all of the developing agent that was resident in the emusion gets used up and there is no agent in B to replace it. When agent and activator are kept separate oxidation is less likely to occur.

 

Bob

[lex_jenkins]

Robert, if I understand one of Dan's goals correctly, one reason for this project is to facilitate the processing of multiple rolls simultaneously. Lifting and agitating a tank containing three or more reels, plus the liquid required to cover them, is not easy for some folks.

 

While Hewes reels are excellent the reel design isn't the primary consideration here.

 

Also, a successful and economical homemade dip-'n'-dunk processing design could be useful to others.

[discpad]

Actually, the processing would be done one roll at a time in sequence, though she could do them back-to-back.

 

 

The idea is for her to drop a roll of film in, put the cap on, and walk out. Then, come back in 3-4 minutes, go dark, move the film from A to B, load another roll of A, put the caps back on, and come back in 3-4 minutes, etc...

 

 

I'm building it with five, possibly six tubes, to give flexibility. So far, the steps will be Dev A, Dev B, wash, fix, wash, wash, one tube for each...

[friedemann_wachsmuth]

Did this actually ever became reality?

 

I am considering something similar for Super-8, as an improved "pull-through" version of <a

href="http://www.peaceman.de/inhalt/schmalfilm/super8/HT-Rohr-Super8-

Entwickler.en.html">this</a>...

 

Too bad that the thread stopped, I love such creative new approaches.