CombiPlan and R5 Monobath in lit room, best practices.

[Lenrick]

I have now developed a few sheets of Atomic-X film in R5 Monobath using a CombiPlan tank. Here are some thought if anyone else is thinking of doing the same (or something similar). I’m sure there are better ways of doing some of the things that I suggest, and perhaps a few steps can be eliminated.

One should note that the New55 Company has recommendations on how to best use their monobaths. One such recommendation is “In darkness, quickly immerse the exposed black & white film in the [monobath]...” I have no way of following this recommendation and must find a route which works in lit rooms.

One recommendation that I try to follow, however, is the following: “Avoid pouring the warmed monobath into a cold tank; streaks may result from temperature differentials and turbulence.”

My recommendations:
1) Do not develop 6 negatives in a single run, but a maximum of 4. The 2 inner slots must be occupied by film in order to protect the outer 4 negatives from pouring liquid. Make sure the emulsion on your 4 negatives are aligned to face the walls of the tank.
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2) Make sure the tank is at the desired temperature (24C / 75F) by letting the tank float on water with that temperature before adding the monobath (do not forget to flip the tank to make sure both sides are at the desired temperature).
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3) Add the liquid through the side-port so that the air can escape through the lid-port. Find the optimal angle for the tank, since horizontal position is not recommended. In horizontal position the liquid will go directly onto the negatives, plus you need more than 1 l of liquid for horizontal position. At the optimal angle, the 1l-bottle from the New55 web store is enough.
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In the figure below you can see some of the artifact that can be avoided using these instructions.
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[Lenrick]

In the figure below you can see an image developed using these instructions.
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[Bob Salomon]

Take the top off your tank and look at the top edge of the tank, see the trough on the top? Now look at the bottom end of the Light Tight Hose Connector. See the opening for the chemistry?
When you fill from the top the chemistry goes through that opening and into the trough where it then runs down the side of the tank and not directly onto the film.
When you fill from the side the chemistry will run down the film.

[Lenrick]

Yes, you are right. But it takes too long time to fill the tank the way it was intended. Much much too long time, for my taste. The air does not escape fast enough.

Filling from the side port when the tank is angeled works better, I think.

[Bob Salomon]

Yes, you are right. But it takes too long time to fill the tank the way it was intended. Much much too long time, for my taste. The air does not escape fast enough.

Filling from the side port when the tank is angeled works better, I think.

Do you open an air path by giving the Light Tight Connector a half turn before filling?

[Lenrick]

Yes, yes I do...or did rather. I stopped filling the tank that way a long time ago, since I thought it took too long.

But to be fair, I have never measured the time it takes to fill the tank through the lid-port (with the port turned to "open"). I'll time myself soon, and compare that to filling the tank through the side-port (with the tank at an angle so that the liquid do no run over the negatives).

Maybe I'm simply biased, some solid numbers should be helpful.

[Bob Salomon]

Yes, yes I do...or did rather. I stopped filling the tank that way a long time ago, since I thought it took too long.

But to be fair, I have never measured the time it takes to fill the tank through the lid-port (with the port turned to "open"). I'll time myself soon, and compare that to filling the tank through the side-port (with the tank at an angle so that the liquid do no run over the negatives).

Maybe I'm simply biased, some solid numbers should be helpful.
You should find that the fill through the top and empty through the bottom times are the same as long as you open the air path on the top each time.

[scheinfluger_77]

I have had good luck on the Combi's by filling via a funnel connected to a vinal hose connected to the bottom port, with the tank in its upright position. Still takes about 30 seconds to fill but until I started doing this I would get random flow marks on the film. I was not using a monobath.

[Lenrick]

Interesting solution, Scheinfluger_77. Thanks for the tip.

How do you remove the hose in order to plug the port when the tank is full? Without causing a huge mess, I mean, assuming the hose is also full of liquid when you remove it. Or du you simply plug the hose when you agitate?

From my experience, the R5 Monobath is not forgiving to work with. But I would recommend everyone to try it because it is fun and will probably help you find "hidden" flaws in your current routine.

[scheinfluger_77]

Simple. I tip it over on its back, remove the hose, cap the hole, and go back to upright position. Yes there is a little bit of chem slosh but better that than processing marks in my view.

[Lenrick]

I have those numbers, Bob, and I must confess that the differences are small enough to give you right concerning the time it takes to add the liquid. I'll probably compare the standard vertical method with Scheinfluger_77's hose method using R5 Monobath and Atomic-X. Since the Monobath is so unforgiving, any "flaws" in either method should be quite visible on the negatives.

The time it takes to fill the tank through the lid-port (the tank in standard vertical potion):
With air path in closed position: 1 min and 15 s
With the air path opened by half a turn: 27 s
With the air path opened by two turns: 27 s

The time it takes to fill the tank through the side-port (the tank laying in horizontal potion)
With air path in closed position (but no plug): 24 s

Are these numbers similar to your experience Bob?

[Bob Salomon]

I have those numbers, Bob, and I must confess that the differences are small enough to give you right concerning the time it takes to add the liquid. I'll probably compare the standard vertical method with Scheinfluger_77's hose method using R5 Monobath and Atomic-X. Since the Monobath is so unforgiving, any "flaws" in either method should be quite visible on the negatives.

The time it takes to fill the tank through the lid-port (the tank in standard vertical potion):
With air path in closed position: 1 min and 15 s
With the air path opened by half a turn: 27 s
With the air path opened by two turns: 27 s

The time it takes to fill the tank through the side-port (the tank laying in horizontal potion)
With air path in closed position (but no plug): 24 s

Are these numbers similar to your experience Bob?
I have never timed the fill time without opening an air path as stated in the instructions which were printed in English, Swedish, German, French and Spanish. So I can not confirm that. I also never tried filling from the side as that lets the chemistry randomly fall on the film while you can't cause that from top filling.

27 seconds sounds about right. You should also be aware that all Combi tanks, those for roll film as well as the 45 daylight versions were designed to leave an air space in the tank so that when the tank was inverted the chemistry could flow over the film rather then just stay in constant contact with the film. So don't overfill the tank.

[Tobias Key]

I have a combiplan tank. One of the things I have found is that if you load the tank upright it is best to stick to only opening the airway half a turn as recommended in the instructions. If you open it wider you may get faster filling times but you increase the risk of splashing on the negatives creating spots of uneven development. For me this totally counteracts any benefit you might get from faster filling. The most successful method for me is to make sure the developer fills at an even pace, no stops and starts caused by overfilling the funnel. I only use quite dilute developer so that development times are around 10 mins or longer, R5 monobath seems to me to be totally unsuited to the combiplan tank if you use the daylight fill, it is way too active. What you could do is buy a calumet dark tent like this one


https://www.calphoto.co.uk/product/Calumet-Changing-Room/RM1000 (https://www.calphoto.co.uk/product/Calumet-Changing-Room/RM1000)

and then work out some way of splash proofing the bottom. That would give you a way of immersing the film instantly.

[barnacle]

On the filling times: with the air port closed, filling the combiplan from the top takes me over a minute; with it open, thirty seconds 'give or take' depending how high up the funnel I let the fluid get.

Which confirms some of the numbers given above. It's the main reason I've stopped using the combiplan; the drain takes the same time so, to my mind, the top of the film gets a minute less than the bottom in the soup, graduated over the height - assuming everything is done in the vertical position. I used development times of eight minutes, so that wasn't a serious issue, but I wouldn't have wanted to use a time much smaller.

Neil

[Lenrick]

I developed some Atomic-X in R5Monobath using the CombiPlan following their instruction (vertical tank, filling through the lid-port, air way opened half a turn). The images turned out fine...making the first post in this thread a bit...well...unnecessary.

I did not see any differences between the parts of negative in the lower parts of the tank (longer time in contact with the liquid) and the parts of negative in the upper parts of the tank (shorter time in contact with the liquid). If there is a difference, it is by no means obvious.

The image below is made from two 4x5" negatives. One very simply pasted on top of the other in Photoshop followed by a very simple (about 10 pixel wide) blurring of the line where one negative ended. The two negatives were placed in the tank in such a way that the left side of one negative was in the lower part and the right side of the other was in the lower part. I assume that one would see the blurred line as a fairly sharp change in tonality if the there was a significant difference between top and botton of the tank.

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