Developing two films at once

[MelanieC]

Before I go and ruin two rolls of film at the same time, I want to make sure of something. If I have been, up to now, developing single rolls with enough chemicals to fill a two-roll tank anyway, do I need to do anything different to develop two rolls in the same tank? My assumption is no and nothing I have read thus far indicates otherwise, but I thought I'd address the question to the experts before proceeding.

Comments?

 

[back alley]

a patterson tank right?
on the bottom of the tank it will tell you that 2, 35mm rolls require 20 ounces.

if you have been putting 20 ounces in then you're good to go.

joe

 

[eric mac]

Assuming both rolls are the same, there shouldn't be any difference unless you are using an extremely dilute solution. There may be a lag time in filling the 6 roll tanks, but a double roll tank shouldn't be a problem.

Eric

 

[bmattock]

20 oz? My Patterson is metric. 690 ml. I always use 700 to be save.

Best Regards,

Bill Mattocks

 

[MelanieC]

Rad. I don't know if I've actually been putting in 20 oz. Just that the tank is full (or at least the bottom part that contains the film is full -- I don't fill up the top part -- maybe I should?).

I'm not very good at being precise, which can sometimes be a problem in a molecular lab but thus far has worked out OK for developing Tri-X.

Thanks!

 

[bmattock]

I use a cheap plastic graduated cylinder to measure out my D-76 or Diafine prior to pouring it in the tank. I don't want to waste it, particularly if it is 1+1 D-76 and therefore a one-shot for me. I also take that opportunity to take the temp and make sure it is within parameters. It's not that a huge level of precision is needed - just makes it more repeatable time after time. Like bracket racing when I was in high school - it wasn't about fast, it was about consistant.

Best Regards,

Bill Mattocks

 

[tedwhite]

Melanie: No difference. If you have a 20 ounce tank, always fill it with 20 ounces regardless of whether you're developing one or two rolls. If only one, make sure you put in a blank spool to take up the extra space so the film doesn't get banged about from one end to the other when you rotate during periodic 'agitation.' I don't like that term, it sounds too vigorous. I rotate the tank in my hand gently every thirty seconds.

I use old stainless steel Nikkor developing tanks, D76 1:1 at 68F. Always filled to their stated capacities (I have a 2 roll, 4 roll, and an 8 roll).

 

[joshmlevine]

Hi Melanie,

When I develop using Patterson tanks, I only fill with enough chemicals to cover the reels in the tank. When developing one roll of 35mm I fill with 290ml of chemicals, two rolls 580ml etc (it is possible to round to 300ml for each roll making life easier).
I believe that this is what the instructions (see copy here ) call for, and has worked to date.

 

[Goodyear]

Hi Melanie,

When I develop using Patterson tanks, I only fill with enough chemicals to cover the reels in the tank. When developing one roll of 35mm I fill with 290ml of chemicals, two rolls 580ml etc (it is possible to round to 300ml for each roll making life easier).
I believe that this is what the instructions (see copy here ) call for, and has worked to date.

That is my normal practice, and I've never had any problems.

 

[BJ Bignell]

Yeah, just make sure you have enough chem. It really sucks when you only partially develop one-half of the top roll. Really, really, sucks...


Sigh... I'm still upset with myself for ruining that roll of vacation pictures. It's been almost a year since, but it was 13+ hours of driving one-way to get there!

 

[Goodyear]

Yeah, just make sure you have enough chem. It really sucks when you only partially develop one-half of the top roll.

Done that, though.

But it was a tank full of film, just mis-measured the dev.

🙁

 

[MelanieC]

Thanks all. I can't remember if I reported back or not, but I developed two at once and it worked.

I'm using some generic version of D-76 and I think I have it diluted to the equivalent of "full strength" D-76 (once mixed up of course). I've reused it for four rolls and as far as I can tell they all look the same. I'm going to dump it before I develop again though because it's turning grey.

 

[taffer]

Btw, if by any chance someday you'd like to develop two different films in the same tank, Diafine is the name 😉

As a rule of thumb, when doing the inversion I always like to hear a 'blurp-blurp' which means developer is indeed moving enough as I invert the tank. If I hear nothing at all, I filled it too much.

Oscar

 

[f/stopblues]

Hey, not to hijack this but I have a related question. A member recently mentioned that its a good idea to add 10% of time for 120 film as compared to the same film in 35mm. I equated that to the size of the film, but would that apply to developing two reels of 35mm in a tank? Why or why not? Thanks!

 

[sf]

How about developing 5 rolls at once? I am thinking about doing that with a big patterson to save money and time. Will the lag while pouring in the mixture cause trouble?

 

[kaiyen]

I'm using some generic version of D-76 and I think I have it diluted to the equivalent of "full strength" D-76 (once mixed up of course).

I've not heard of any version of D76 or any clone that is mixed up to full strength. When it's mixed from powder, that is stock or full strength. You then dilute it to working solution, usually 1+1 but sometimes 1+3 if you want more acutance. I am interested as to what you are doing here...

I've reused it for four rolls and as far as I can tell they all look the same. I'm going to dump it before I develop again though because it's turning grey.

I'm also not aware of any D76 or clone that should be reused. One-shot only.

Hey, not to hijack this but I have a related question. A member recently mentioned that its a good idea to add 10% of time for 120 film as compared to the same film in 35mm. I equated that to the size of the film, but would that apply to developing two reels of 35mm in a tank? Why or why not? Thanks!

1 roll of 35mm is the same area as a roll of 120. So you don't technically need to make any adjustments between the two. However, for some reason and I've noticed this, too, I feel like I'm not getting the same contrast with 120 as I do with 35mm. I add about 10% with 120.

 

[kaiyen]

How about developing 5 rolls at once? I am thinking about doing that with a big patterson to save money and time. Will the lag while pouring in the mixture cause trouble?

In a Paterson tank you can fill and pour so quickly you're usually okay. The amount of time the bottom reels get extra soup while pouring in is negated by the time the upper reels get while pouring out.

It's a bit different with steel tanks, as it's much, much slower to fill and empty those tanks. People recommend that you fill the tank first, then lower the reels in (in the dark, of course) for steel tanks.

allan

 

[T_om]

How about developing 5 rolls at once? I am thinking about doing that with a big patterson to save money and time. Will the lag while pouring in the mixture cause trouble?

Not with Diafine.

I still have one 8-reel tank left. It is going in the for-sale forum though because I have so many 4-reelers kicking around there is no point in keeping it. It is the last of 4 I had. Yeah, I used to develop a LOT of film at one time.

Tom