In tank mixing of Rodinal concentrate?

[michael_schiller]

Hi All.

 

I have a simple question. I develop mostly 4x5 sheet film using either a Nikor tank/reel or

an HP Combitank. Both of these are daylight tanks that have fairly small openings for the

filling of chemicals, so the normal recommendation is to use a water bath before adding

developer. I was wondering, if it would work to use say Rodinal, and actually use the in

tank prewet water to mix the working solution? As an example, using the Nikor tank which

holds 40oz of chemical, to use a 1:25 dilution would mean adding 1.5oz of Rodinal to a

presoak of 38.5oz. Is there any reason that the initial agitation wouldn't mix the solution

fully?

 

-Mike

[peter_dendrinos1]

Michael,

 

I don�t believe you will get optimum results using this technique. The obvious reason being that you will have varying concentrations of developer solution coming in contact with the film. Normal agitation with a loaded tank will not allow for proper chemical distribution within a short enough period of time.

[eduardo_benavidez1]

Guess a procedure as follows: 1) Trown in the Rodinal as quickly as possible while agitate the tank as much as possible; 2) continue your normal initial agitation step. I´ve used that system on Paterson tanks with no uneven development problems. Eduardo.

[jeff_drew4]

I've done it successfully with sheetfilm. I generally use a syringe to measure the Rodinal and inject it into the water, then "shake-it" briskly. Just don't get distracted 1/2 way thru procedure. Generally I use the pre-soak, then a fresh Rodinal/water solution at proper temperature for better consistency, tho'. sometimes shortcuts work okay, but eventually I have missed a step and pay the price.

[amul]

I'm gonna side with Pete on this one. The first 30-60 seconds are the most critical, and you want the developer to be evenly distributed during that period.

[chris_waller]

I would advise against this. For optimum results it is essential that the developer is thoroughly mixed before pouring it into the developing tank.

[jeff_drew4]

I agree. I only 'fessed up because the shortcut can work sometimes. Consistency is what we strive for, tho' and skipping recommended steps in any process increases the risk of failure. The idea of raising temps on solutions to speed up processes has bitten me on the butt numerous times too . . . but then there were publishing deadlines etc. Michael ask yourself, "Given that Rodinal is a popular, very old and mature developer, why aren't the instructions and recommendations written to include my idea(s) ?"

[patrick_gainer]

I've never tried it, but I'm wondering why it is any worse to pour in the concentrate than it is to pour in 40 oz. of ready mixed developer. That certainly won't go in all at once. Some of your film is going to get longer development in any case. Even if you pour in the developer and then drop in film holders of one kind or another in the dark, the film will not be immersed all at once. I think the guys who have done this shameful deed of adding concentrate to the tank are not telling all they know. I think the ones who advise against it have never tried it and are talking from theory rather than experience.

 

But then I'm a mean old man who is in my second (or is it third?) childhood.

[jeff_drew4]

Patrick, . . . touche'! I do Minox in Minox tanks that are designed so that they work

best when the thermometer in the center is used as a plunger to circulate the

chemistries. The tank is very small and rugged, but the concept works great. So I

deviated from the recommendations and got mixed results - a few that cost me some

frames, but I don't exactly follow the instructions as my grasp of German is very poor

- my German mother would agree! :-) The Nikor tanks are terrific. One can hoist'em

and shake'm just like martini shakers! If one pre-soaks, adds Rodinal quickly, and

shakes it 'til the cheeks wiggle, and then rests, the mix is probably distributed quickly

and evenly. If one delicately pours the Rodinal in, gently wipes the tank lip with

mom's favorite linen, and sits and watches the tank - no agitation, then the results

will be inconsistent or even crappy. What the heck, Mike, give it a try and find your

own ways. Remember, "Shaken - not stirred!"

[nige_buddy]

Just a little story...

 

Though an act of stupidity (I was explaining the process to someone as I developed their film!) I once managed to pour my concentrate into the tank (Paterson System 4) rather than the beaker I was supposed to mix it in! I quickly added about the required amount of water and agitated like crazy. The negs came out fine but I'm not sure my friend thought I knew what I was doing! The reason I think I got away with it was I was using a 1:29 dilution so the 10ml of concentrate must have lay under the film before I added the water. We ended up making some nice prints from their negs, so all was well :)