Combi Plan dev tank teething problems

[Kevin Kemner]

Baxter,

Here are the things I've found work best with the Combi Tank.

1) I can't figure out if you're using the slot guides when you load film. If you don't have them then you need to get some from HP Marketing. 2) The film has a tendency to dislodge during agitation if the retaining clip is on too tight. The clip should only slide down until it contacts the film. Otherwise the film is distorted and the chemical movement will push it into the next slot.

3) Because of the slow fill and drain the tank is best used with development times longer than 8 minutes. Agitate for the first minute after the tank is filled and then for ten seconds every minute after. I start the timer when I BEGIN to fill the tank and don't start to drain until after the timer has gone off.

4) To best avoid agitation marks face each sheet of film AWAY from the center spine. The spine will cause a linear mark if the inner sheets of film are facing towards it.

5) Wear gloves.

I've been using the tank for about four years and get very dependable results. Like every development technique you will need to refine your times to get your desired results.

Good Luck

[Bob Ashford]

Hi, Please persevere, I have been using mine for about 6 months and I am very pleased with the consistant results. Yes you have to get to know it and I agree with Kenvin - we work in exactly the same way. Best regards Bob

[Allan Fontanilla.com]

Fill and drain from the bottom spout only. Use the spout that's on the lid as the vent only. Remove the cap on this vent when filling and draining for air passage. This way you will never have to loosen the vent at the threads.

[Bjorn Nilsson]

Hi!

About the film and retaining clip of the CombiPlan, I can only agree with the other answers that you find. Practice! Most of the procedures taking place in the dark are rehersed beforehand. Think of it as entering a new darkroom. I guess that you would like to get aquainted with it while the lights is on. (The same goes for most girls as well. :-)

Some people have reported problems with uneven developing in the CombiPlan. I guess that this has to do with the agitation pattern. It isn't a matter of turning the tank very quickly, rather to make sure that the developer "sits" when the tank is turned upside down. I also shake the tank in an irregular pattern now and then, as part of the agitation schedule.

The CombiPlan is very slow to drain/fill. Here's what I do:

I fill the tank with the 1 liter of developer needed and put it at its place. I then load the film in the holders and when I feel like I'm all done and I got my bearings, I dump the holder into the tank and then on with the lid. It is easy to time the time it takes from the dumping of the holder into the tank, through putting on the lid, putting on the light and starting the timer. That time should be subtracted from the total developing time. Of course this takes knowing exactly where everything is, i.e. practice again (and again...)

About 40 seconds before the end of the development time, I start to drain the developer. It is the stop bath (or possibly fixer bath for those who cannot afford the stop bath :-) that will stop the development, not draining the developer half a minute before. Besides, the developer is least effective in the end of the development.

Now, if you can subdue the light to a very low intensity, i.e. almost dark, you can lift half of the lid and pour on the stop bath directly. The same thing is recommended with the BTZS tubes, and it works the same here. There is no (or almost no) sensitivity left in the developed film. But please note that (Check www.darkroom- innovations.com for the instructions for BTZS tubes.) The same of course goes for the following baths, i.e. fixer, hypo-clear etc.

When the film have gone into the fixer, you can turn up the lights, even if the lid is off. If you feel uncertain about this, keep the lid on for a minute. Then there is absolutely no way that the film will be damaged in any way.

For washing I normally have the bottom funnel open and have the water running just a little bit faster than the funnel lets out water, so that a little water runs over the top. I also dump the tank a couple of times.

I havn't done DiXactol, so I havn't a clue about the staining part. But I guess that light doesn't play a part in the staining, so it is probably OK doing it in an open tank with the lights on.

[Bob Salomon - HP Marketing]

"A bit off the point, but a useful tip which was passed along to me and works quite well: once you get the hang of loading the film, you can cut plastic screening to the size of the film, and load 2 sheets, non-emulsion side of each against the piece of screen, into each of the slots. This allows you to process more than 6 sheets at a time (up to the limits imposed by proper amount of developer per sheet). "

Two things.

1 Only do back to with black & white. This does not work for color. 2: The screening is not necessary. This is an idea used for teaching 45 processing at the Univ. of Montana and does make it easier for some to do back to back processing. It is usually done with fiberglass screening and not plastic or metal screening. Fine mesh window screen is best.

As to the comment about filling from the bottom. This can be a good way to cause streaks. The top is designed for the chemistry to fill from the edge of the tank when it is poured into the Light-Tight Hose Connector. The bottom does not have the flange to direct the chemistry flow.

Lastly this is an inversion agitation system designed to be used with a tank that is not 100% full of chemistry. It was designed for the chemistry to flow. That means invert and don't shake.

Of course, like any tank system, after filling it should be rapped to dislodge any air bubbles from the surface of the film. This is done by gently tapping it a couple of times on a table top after filling.

This is possible the oldest 45 daylight processing system made. Before we purchased the tooos from Gepe in the late 70s it was the Gepe Combi-Plan tank. Gepe purchsed the tools from the inventor of the system "Krause" who introduced it in the 30's or 40's in Europe. It is also sold as the Linhof System as they had distributed it in Germany for several decades

[Charlie Skelton]

The chap I bought my tank from advised a larger funnel for quicker filling. I always use dilute development (20-30 mins) however which largely renders the point moot. I have had problems with marks at the top of negs and I now generously fill the tank with developer. Charlie

[dan nguyen]

Hello Baxter...

I use the Combi Plan and I like it more than any other system. Yes, in the begining I had the same problems as you do now but with practices they went away... all the above suggestions are excellent specially the the 2 tanks method..here is how I do it... 1. for loading film, I use the guide and recheck like a blind person... 2. since I hate the slow filling (which wrecks my development time), I pour in advance the developer in the tank and leave it there. After loading the film I just dip the whole rack of film in the tank and close the lid and switch on the light, tap a lot (for bubles) and shake accordingly...when time is up I switch the light of, open the lid and empty the developer. 3. repeat the same for water rinse and fixing but it is not as critical as for developer, which mean you can use funnel as indicated by the manufacturer... hope this help....

[Rob Pietri]

I hope this is not a double post. I posted a response that has not shown up so I'll try again.

I use the Combi system though not as recommended by the manufacturers.

1. I have one tank for each step; presoak, developer,stop,fixer, hypo clearing agent, wash, foto flo, and use it as a dip and dunk system. The funnels and top valves should not be used because the chemestry takes too long to fill, causing bubbles and streaks. By having a tank for each step, you can just lower the film holder in and out each tank.

Still, if you wish to use one tank, just have the succeeding chemestry ready and waiting to pour in with the lid off. Obviously this has to be done in total darkness. I do use the lids for each step so I can turn on the lights.

2. Loading the film takes a little practice. I do not double up but only process 6 sheets at a time. My systems came with plastic guides that are placed ontop of the film holders. Once the sheets are inplace, they are removed, and the holding clip put in place. Be careful not to press down too hard with the clip, but just far enough to touch the top of the film.

3. The agitation is very important. I invert the tanks with the axis through the wide part of the tank, so that the narrow part turns end over end. This way, the weight of the chemestry is on the edges of the film and not the flat part. This will keep the film from jumping the channels. Shaking can cause bubbles.

4. I have one tank with a rubber stopper that has two holes, inserted in the drain. This I use for washing, the water from top and out the bottom at an acceptable rate exchange.

I used to use trays but find using tanks gives far more even and consistent processing. As for Jobo, many noted pros swear by them and if you can afford one and all the tanks, gears, cups, etc, go ahead. But you will find you will have to get used to that system as well.