A quick question about dev tanks

[defconfunk]

When developing a single roll of film in two roll tank, I'm assuming you put both reels in to stop the film from moving about, but do you use half the normal amount of liquid (ie the amount you'd use in a single roll tank), or do you have to fill the tank? Does using only half the liquid cause issues with inversion and bubbles forming?

I'm looking at developing my own B&W, and since I would like to be able to do two rolls at a time, or MF, I plan to get a two roll tank. But, since I have a number of rolls that would need to be developed individually, I'm wondering how I would go about that.

Thanks

 

[kmallick]

Its smart to get a two reel tank. You can use wither an empty reel or you can get a slip on ring like this that snaps on the collar and stops the reel from moving up the collar during inversion.

The amount of liquid you use depends on what keeps the reel submerged (typically whatever is mentioned in the bottom of the Patterson tank for each reel).

 

[zauhar]

To avoid confusion, I generally use the two-reel volume even when developing a single roll, as I have in mind volumes of rodinal or hc110 I need. I know that is wasteful.

Randy

 

[KenR]

I also use 2 reels in the tank even if it's for a single roll of film and generally use the chemistry for 2 rolls as well. My feeling is that with the tank only half full there will be much more sloshing around of the developer which will lead to over-development. Therefore, in trying to keep things standardized as much as possible, I avoid that by using the same amount of developer in the tank, as if there are two rolls on two reels. (But I have never done a test to see if really is an issue.)

 

[Dwig]

When developing a single roll of film in two roll tank, I'm assuming you put both reels in to stop the film from moving about, but do you use half the normal amount of liquid (ie the amount you'd use in a single roll tank), or do you have to fill the tank? ...

It depends on the type of tank and, primarily, the type of agitation.

If you agitate my inverting the tank then regardless of the type of tank you must fill the tank with chemistry. If your tank has provisions for stabilizing a single reel you can use only one reel but if it doesn't (e.g. standard stainless steel tanks, ...) you must also fill the tank with reels.

If you are using a tank with spin-the-reel agitation they you can only use enough chemistry to cover the single reel.

 

[nikon_sam]

I normally use just the reels that are loaded and use the recommended amount of developer per reel (rounded off) If 290ml I'll use 300ml...easier to mix solution...
The Paterson tanks are labeled on the bottom...If I'm developing one roll I'll use the amount for one roll...I've never had a problem with doing it this way but I know that others may have...
Recently started using a SS tank and doing it the same way with this one...so far so good...

 

[kxl]

I just shoot another roll of film. 😉

 

[nikon_sam]

I just shoot another roll of film. 😉

Yeah, well, then there's that...😱
I would rather do two (120) or three (35mm) at a time when I develop...it saves time...
I was testing some filters the other day and just did the one roll, then after I found another exposed roll...:bang:

 

[defconfunk]

I just shoot another roll of film. 😉

The problem with that is then I have to do things in pairs. If I want to push a roll, I need to wait for (or shoot) two pushed rolls. Right now, since I'm still experimenting with film, I have 6 different rolls of B&W film. When I standardize on preferred film (and start bulk loading), then it'll largely be a non-issue.

I suppose using twice the chemicals isn't exactly the end of the world. I would just prefer not to waste chemicals (I'm cheap that way).

 

[loquax ludens]

I try to fit the amount of film I have to the tank. A single roll tank for one roll, a two roll tank for two rolls. A four roll tank for 4 rolls of film. If I have 3 rolls, I usually put them in a four roll tank and leave the top reel empty. I reduce the volume of chemicals accordingly, and agitate as normal. I haven't seen any ill effects from doing this.

Of course, this assumes all films need the same development. Otherwise, you have to split them up as required for proper development anyway.

 

[V-12]

If you agitate my inverting the tank then regardless of the type of tank you must fill the tank with chemistry.

The whole point of inversion is to keep the developer mixed and to replace used developer with fresher developer on the film surface. If you fill the tank with developer it negates the replacement of developer because it doesn't move, or at least doesn't move as much as it should. Think of it this way, if you fill a bottle full of water and put the cap on, then turn it upside down, the water that was at the top of the water column doesn't rise back up to the top again, it stays where it is at the bottom.

 

[fidget]

My pattern was to develop one roll in a double tank, with the ring or empty reel loaded to stop the loaded reel moving. With a little extra dev in the tank I would then dev a second roll in the same mix (poured into an different tank). I saw no problems or changes in development, but then my workflow was never based on very accurate parameters, tending to use a collection of cameras.
Dave

 

[john_s]

2 reels in a 2 reel tank results in fairly gentle agitation (assuming inversion). 1 reel in a 2 reel tank with enough developer to just cover the 1 reel gives fairly vigorous agitation unless you think about it and invert it gently.

The only caveat would be with very dilute developers which might oxidize quickly like PMK. Then the extra air could cause premature exhaustion of the developer. When I used PMK I tried to leave a rather small amount of air in the top of the tank.

(It goes without saying that you do whatever it takes to stop the one reel ending up being dislodged from the bottom of the tank.)

 

[print44]

I use a Patterson double tank. With 35mm I often put the second (empty) reel above the loaded one to stop movement, but still use 300ml of solution. However since experimenting with semi-stand and stand development I've come to the conclusion that very gentle inversion about 3-4 times per minute is better than more vigorous inversion every half minute. As a result the single loaded reel doesn't really move up the plastic hub during development. For fixing I always use 500-600 ml.

For 120 I load 2 films onto one plastic reel using the sticky tape from the end of the first roll to tow the second into the reel. This works well I've found.

One other thing, I always always trim the corners off the leading edge of both 35mm and 120. This makes them significantly easier to load into the plastic Patterson reels which I find difficult to get completely bone dryfor a second run after an initial process.

 

[hamradio]

For 120 I load 2 films onto one plastic reel using the sticky tape from the end of the first roll to tow the second into the reel. This works well I've found.

Oh, that's clever. thanks for the tip!

 

[Dwig]

The whole point of inversion is to keep the developer mixed and to replace used developer with fresher developer on the film surface. If you fill the tank with developer it negates the replacement of developer because it doesn't move, or at least doesn't move as much as it should. Think of it this way, if you fill a bottle full of water and put the cap on, then turn it upside down, the water that was at the top of the water column doesn't rise back up to the top again, it stays where it is at the bottom.

Of course you don't fill the tank to the brim. There is a proper fill level for any tank used with inversion agitation and that level must always be the same regardless of the amount of film actually in the tank.

The critical point is that ANY change in the tank's chemical loading and ANY change in the amount of movement of the film reels will significantly alter the affect of the agitation totally ruin any control or consistancy you might have.

 

[defconfunk]

So, I've developed a couple (literally, two) rolls now. I used 350ml of all fluids, and loaded the bottom reel. So far it has worked out well. Now I just need a couple of extra plastic reels so I can do a 'batch' of single roll developments (since I only have two reels, and I can't load them when wet, I wait a day between developings. Thankfully stop and fixer last that long mixed).

I was lucky and picked up a used AP 2-reel tank and a steel 2-reel tank (with a 120 reel as well). I have to say, the AP 'classic' reels (what I have) are SO much easier to load than the metal spirals. I'm going to need to get good at the metal reels at some point though, since my only 120 reel is a metal one...

And for anyone who is thinking of trying to develop at home - keep an eye on the classifieds for cheap/free old darkroom gear. Coming from digital, the tangible aspect of loading your own film and developing your own negatives is pretty awesome.

 

[MartinP]

You will almost certainly find that all the 35mm plastic reels have three possible sizes when clicked together. These 'clicks' are for 35mm film, 127 rollfilm and 120 rollfilm.

 

[Mcary]

So, I've developed a couple (literally, two) rolls now. I used 350ml of all fluids, and loaded the bottom reel. So far it has worked out well. Now I just need a couple of extra plastic reels so I can do a 'batch' of single roll developments (since I only have two reels, and I can't load them when wet, I wait a day between developings. Thankfully stop and fixer last that long mixed).

.

Just an FYI Once I mix a working batches of Stop and fixer I generally use it for 10 tanks (1 roll of 120 each) or a month which ever comes first, before mixing new batches. Based what I've seen others post here on RFF that's pretty conservative.

 

[nikon_sam]

It's always good to have lots of reels...I have more tanks and reels than I need at any one developing session...just something most of us have done over the years...
But when I was just starting out and I needed to develop more than a few rolls in one day I would use a hair blow dryer to completely dry out my reels...you don't have to set it to the highest heat level (plastic reels not too happy with high heat) but a medium setting with the highest blower setting usually works...