Amount of solution to use in developing tank

[Todd Barlow]

I have a stainless steel tank that will hold 2 120 reels but leaves enough space for an additional 35mm reel plus another 1/2 inch or so.

When I am processing 2 120 rolls I fill the space with an empty 35mm reel and a plastic disk to keep the reels from moving when I agitate by inversion.

So the question, is the right amount of solution 1) to cover just the 120 reels and leave more than 2 inches of air space or 2) fill the tank and leave some space at the top to allow the solution move around?

Thanks

Todd

 

[Konical]

Good Evening, Todd,

Perhaps there are exceptions for some developers, but, generally, you probably won't detect any difference between the two choices. If I were doing it, I'd prepare about 30 oz. of solution. With most SS tanks, that's enough to cover two 120 reels and a bit more; 32 oz. should cover the loaded reels and a good portion of the empty 35mm reel.

Konical

 

[John Koehrer]

Todd,
It may make a difference in how you agitate. If you invert the tank I don't think you would want that space to be empty. Develper is inexpensive enough not to worry about the cost of a few extra oz. as opposed to potentially ruined film.

 

[jstraw]

I use enough developer to immerst the film and no more. I invert while agitating. I have no problems.

BTW, you describe the space that's left over when you put 2 120 reels into a tank that can hold 4 35mm reels.

 

[reellis67]

Others may do things differently, but I measure by putting empty reels in the tank until it is full and then fill the tank with water to the point that the water covers the top reel by around 1/4 inch or so. I then measure that volume and make sure that I use that volume for developing with either one or two loaded reels, although I suppose that if all you were using was one loaded reel, as long at the volume was enough to cover the bottom reel by 1/4 to 1/2 inch and use that volume. Generally speaking, I would think it might be more convenient to use a smaller tank if your not doing more than couple reels with a tank of that size...

- Randy

 

[brian steinberger]

It seems to me that if the tank was filled to the top with developer that agitation wouldn't be as effective as if there was some room for the developer to move around during agitation.

I fill just to just above the reels as described by Randy. I use 28oz of developer for two reels. Never had a problem.

 

[MattKing]

I try to have approximately the same amount of air space above the developer solution in all my tanks. I reason that if one tank has a lot more air above the solution, than my inversion agitation regime will be substantially different from one to the other.

Of course, if possible, it's best as well to have approximately the same amount of developer for each roll.

I haven't considered whether it might be appropriate to vary the dilution to accomplish both goals.

Hmmm.....?

Matt

 

[Rick Jones]

I honestly believe you can achieve good results with either 1) or 2) as long as you are consistent each and every time. One caution if you are using just enough developer to cover the reel. Most manufacturers mention the minimum amount of developer necessary for each roll to be developed. For ex. Kodak says to use 16oz of D-76 1:1 for each roll (80 sq in) based on their time temperature charts. You may only need 8 oz to cover a single roll. What to do - as long as you are using enough stock solution to develop the exposed silver you will be fine. But you will probably have to develop the film longer (sometimes considerably) than the manufacturers charts recommend. That's a long winded way to say when you use less developer you may have to extend development times. What's long enough - when your highlights are just dense enough so your negatives print on the grade of paper you consider normal.

 

[raucousimages]

I always fill the tank almost to the top with no sort of spacer used and just let the reels slosh back and forth during developement. The times I tried to use just enough developer to cover the reels (30 years ago) I had a problem with getting marks from bubbles on the film. A lot of pepole just cover the reels with no problems. If the negs look good, with even developement and no bubbles there is no reason to fill the tank but other than using more developer there is no reason not to fill it. All you need to care about are good negs however you do it.

 

[reellis67]

Most manufacturers mention the minimum amount of developer necessary for each roll to be developed.

I've read that you need quite a bit of Rodinal per roll/sheet (something like 10ml !), but I've gotten very good results using as little as 2ml. By good I mean that if I compare the negatives made using 2ml and those made using 10ml *I* cannot see the difference, in either print or negative. I will not say that all manufacturer recommendations are marketing oriented, but I will say that I think both marketing and the desire to err on the safe side play are large part in those recommendations.

- Randy

 

[PatTrent]

I have a stainless steel tank that will hold 2 120 reels but leaves enough space for an additional 35mm reel plus another 1/2 inch or so.

When I am processing 2 120 rolls I fill the space with an empty 35mm reel and a plastic disk to keep the reels from moving when I agitate by inversion.

So the question, is the right amount of solution 1) to cover just the 120 reels and leave more than 2 inches of air space or 2) fill the tank and leave some space at the top to allow the solution move around?

Thanks

Todd

I've always filled my tanks to the brim (for 35mm and 120, and even when I used an HP Combi Tank for 4x5) and I've never had any problems with uneven development or air bubbles, etc. I always fill the tank with reels--loaded or unloaded, and pour in at least the tank's liquid capacity of developer. Usually the developer overflows, as I use highly diluted HC110 and Rodinal. Works for me.

 

[reellis67]

One of the problems with filling the tank to capacity is that there is not enough air space to create flow during agitation. There should be *some* space for the solution to move so that there is an exchange of 'fresh' developer for 'old' developer at the surface of the film. In all cases it is my opinion that if your system works for you, stick with it - unless of course you like to experiment.

- Randy