Film to Developer Ratio

[mikeryan]

I was wondering if there is any difference/effect on film if one develops say a roll of film with 12 frames in 350ml of chemistry versus a roll of 36 frames in the same ammount of chemistry? I am bulk loading and wanted to do smaller rolls and was wondering if there would be a different exhaustion rate, etc. As always, thanks in advance for any info on this matter!

Mike

 

[Dave Miller]

Unless you use very dilute developer the answer is no.

 

[fhovie]

It kind of depends on the developer you use. If you are using anything off the shelf (D76, XTOL etc) full strength, no problem. If you are using a weak staining developer it is a little different. Some developers need at least 500ml per 8x10 area of film. A "roll" of film is usually considered one 8x10. I believe 24 exposures of 35mm is likely less than that and 36 exposures possibly slightly more. Hand tanks usually need 500ml to cover the spool so you are always covered there on developing agent needed for the quantity of film. Even D-76 or XTOL at 1:3 might need more than 350ml for one shot use. I would look it up for the developer you are using if you are not using it full strength or 1:1.

 

[srs5694]

Hand tanks usually need 500ml to cover the spool so you are always covered there

Not true of 35mm film. I've got four tanks, two stainless steel and two plastic. With the stainless tanks, I use 250ml per roll, which provides some margin for error (225 would probably cover, but just barely). With one plastic tank (an unusual Russian design), 250ml also covers one roll, but with less margin. With the other plastic tank (an AP design), IIRC 325ml is recommended, but I always use 350ml because it's easier to measure.

With most of these tanks, 500ml will cover two rolls of 35mm film or one roll of medium format film. I believe the AP tank requires a bit more than this for 2x35mm or MF, but I don't recall the precise value.

I've never had a problem I could attribute to too little developing agent when using 250ml per 35mm roll. I've used Rodinal 1+25 and 1+50, D-76 1+1 through 1+4, XTOL 1+1 (and a roll or two at 1+2), PC-Glycol 1+49, DS-10 1+1, and DS-12 2+1. These are all pretty conventional developers (PC-Glycol, DS-10, and DS-12 are home-brew formulas, but they're fairly conventional in design even if they aren't commonly used.) PC-Glycol is probably the oddest of them, and I believe it's got the lowest concentration of developing agents. It's never given me unexpectedly thin negatives, although I've had to test to find appropriate developing times for it with most films, and I'm sure I've gotten thin negatives from underdeveloping when doing such tests.

 

[Akki14]

Paterson tank takes 500ml for 1 120/220 roll, 600ml for 2 35mm, i think technically it's 290ml for 1 roll of 35mm but i prefer round numbers so i do 300ml per 35mm roll.

 

[Roger Hicks]

A couple of thought-experiments are useful here.

1: How much dev is there for a 4x5 inch Polaroid?

2: Consider a 2-bath dev. All the developing agent is normally in bath A. Soak in bath A. Pour out bath A. How much is left behind? Less than 25ml/film, and much of that is wetting the tank, not imbibed in the emulsion. Add bath B, which is activator only... The amount of developing agent per film is minute.

Most of the dev you use is to wet the film quickly and evenly. Unless it oxidizes during the course of development (e.g. PMK) there's always plenty.

I am aware of the Xtol anomaly and wrote to the designers for illumination. They replied, but I fear the answer was not illuminating. It may be that I failed to understand it, but I think it more likely that they did not answer the question.

Cheers,

R.