Combiplan tank - first attempt useless!

Putting this one down to experience, but after putting the negative through the developer and stop, I unscrewed the top cap to put in the fixer..don't know why. I've ended up with a negative that looks solarised! Presumably the tank is not light tight without the caps screwed in place..? Comments appreciated, LOL

Oh well, onto my second negative later..

Question: I have 2 litres of made-up T max solution. Can someone tell me how many 4x5 sheets of film this will develop before it is exhausted?

I think I will quickly move onto tray developing if I can make my kitchen or bathroom light tight.

Regards from a useless newbie on home processing!

Steve

I have used a Combi-Plan tank for over 20 years, and never had a fogging problem. I think pouring in the solutions thru the top cap is too slow, even using the supplied funnel, however you don't unscrew the top cap all the way, you just take off the little friction fit top cap cover, and IIRC just unscrew the cap slightly to allow for air to escape...but that is not the way I use the tank.

My preferred way is to have the developer already in the tank, turn out the lights, load film into hanger, put into tank put lid on, turn on lights, agitate, etc., then when time to pour out the developer I turn out the lights,remove completely the top, pour out the solution, pour in the new solution, replace the top, turn on the lights, and so forth. It goes very quickly. You can either pre-measure your chemicals to ensure you have enough, or you can just stick a finger into the tank, and feel the solution rise above the film as you pour in the dark.

Thank God for this forum! It's like having an interactive teacher at your side. thanks for the reply. I'll give your method a go when I make up some blinds for the kitchen.

Just processed another and it looks ok! the negative had come out of the guides so I think I could have pushed down the retaining bar enough. Still learning.

Another question, sorry. T-max fixer. It says 2-5 minutes, 20 -29 degrees. I assume this means I fix for 2 minutes at 20 degrees? and will fixing it for longer harm the negative?

You are right about filling the tank. It is painfully slow.

Regards

Steve

You'll get it right with some practice.

The fixer (as most other chemicals) works faster and more intense at higher temperatures. But you should settle for one single temperature for the whole process of developing, stop, fixer and wash. Most of us go for either 20 deg. or 24 deg. Celsius. Choose whichever is most convienient for you (i.e. closest to your normal room temperature) and stick to it.

It is difficult to say if you fixed your negatives enough, as the fixing time mostly depends on the film being fixed, the condition of the fixer and the temperature.
If you are using Kodak Tmax or Ilford Delta films you have to prolong the fixing time towards the 5 minutes due to the magenta stain which takes some extra fixing to get rid of. With other films normal fixing time is closer to 2 minutes with fresh fixer.

The good news is that after you have poured in the fixer you can almost immediately lift the top cover in its whole and agitate by lifting and sinking the neg holder. To be on the safe side, do this in subdued light though.
"Why would I do this?" I hear you say.
Because the fixing time is supposed to be twice the clearing time. I.e. the time it takes for the milky emulsion of the negative to go away. With most films in rapid fixer (e.g. Tmax fixer), this happens in between 30 and 90 seconds. So fix for double that time and you're done.

And yes, fixing for too long does slightly bleach the negative, apart from having the negative in the fixer for more time than necessary probably makes the washing time longer too.

Quote:

---

Originally Posted by Gene McCluney

I have used a Combi-Plan tank for over 20 years, and never had a fogging problem. I think pouring in the solutions thru the top cap is too slow, even using the supplied funnel, ....

---

I don't see this as a problem. If you empty from the top cap, empty time is similair to fill time, so each part of the neg is on contact with the dev. for the same amount of time. Besides, it is a lot easier, just include the empty/fil time as part of the processing time.

Steve

I fill from the top. I empty by inverting the tank over a jug and loosen both caps. This empties the tank from the bottom. No problems with uneven development here.

Barry

" I unscrewed the top cap to put in the fixer."

I hope that IS NOT what you did! If so you opened a light path to the film.

The instructions state to LOOSEN the top cap by a slight twist to open an air path - not to remove it which would open a light path and do exactly what you just had happen.

If you follow the printed instructions you will have no fogging or solarizing problems as well as no streaks, air bell marks, bromide drag, etc.

I use the supplied funnel. It takes about 25 seconds to fill the tank. It has not resulted in uneven development - the same with drainage through the bottom. The only recommendation I would make is to not use photo flow in the unit. Over time, the soapy residue seems to build up and alter flow in the tank - leading to streaking along the far edge of the negative where they fit into the channels. Since embargoing photo-flo/lpn from the tank I have not had a recurrence of the problem.

" I unscrewed the top cap to put in the fixer."

I hope that IS NOT what you did! If so you opened a light path to the film.

The instructions state to LOOSEN the top cap by a slight twist to open an air path - not to remove it which would open a light path and do exactly what you just had happen.

If you follow the printed instructions you will have no fogging or solarizing problems as well as no streaks, air bell marks, bromide drag, etc.

"Just processed another and it looks ok! the negative had come out of the guides so I think I could have pushed down the retaining bar enough. Still learning."

Maske sure that the film carrier is properly assembled with the curved film grooves facing in towards each other. NOT THE STRAIGHT GROOVED SIDES! NOT ONE STRAIGHT AND ONE CURVED SIDE!

Make sure that you did not asseble the tank with the blue washers. These should be thrown out if your tank mistankenly came with them.

The film retaining clip is ratched. You will break the clip if you try to pull it off without pushing the sides in while lifting.

If you have straight sides in, one straight and one curved in, the blue washers installed or have broken the clip you will have film possibly fall out during inverse agitation. If any of these are incorrectly installed or broken please correct the problem before processing more film.

"You are right about filling the tank. It is painfully slow."

When you fill the tank twist the top Light Tight Hose Connector to open an air path. When you empty the tank twist the bottom Light Tight Hose Connector to open an air path. Empty and fill timeas are equal when you do this. Make sure to re-tighten them for processing. Use the amount of chemistry that is molded into the chart on the bottom of the top lid. Do Not Overfill!

Something else I noticed is that if you are too aggressive with your agitation the film can pop out of their channels. I just do a couple gentle inversions and that is it.

I've done what Gene does also. It is very easy to keep the holder in the tank with one finger on the top of the film rack while dumping the liquid. Towards the end of the fixer stage, I remove the top and do everything else in the light without the lid like Bjorn says.

I think once you work out a system, you'll really like the tank.

Always invert the tank in the same plane as the film. Otherwise the movement of chemical may wash the film out of the slots.

Barry

I use it much easier!
I only use the Combi as Developer Tank so the soup is in there bevor I start.
Also I have two more tanks where normaly get used to put meat in it or milk or wathever food! they are filled with the Stop or in my case more used Fix and in the third there is the new good fresh fix.
So I only can use the lights during developing and for the rest its dark, but it is much faster and better for each soup hes own tank!
Hope it helps!
Happy darkness, Armin Seeholzer

Hi, I only push the film clip down 1 or 2 clicks.

Jon

HI. I have some advice for using the Combi Plan tank. If you intend to use the tank in daylight I advise agitating the tank by inverting it, holding the narrow sides of the tank. This way the force of the water won't push the film out of the holder. If you rotate the tank holding the broad side of the tank the film will fall out.

I'd like to thank everyone very much for their help and opinions. Tonight I developed 5 4x5's in one go, using standard (not recommended) Tmax instead of RS. They look absolutely fine. In fact one looks quite good :-).

Loading was easier tonight, but I could do with a bigger changing bag (a light tent?), and I think, although the tank is not a failure, I am going to organise blacking out my kitchen or bathroom, and try developing in 7x5 trays if that uses less chemicals.

I worked out the cost. Here in the uk, the cost of one 4x5 sheet and the chemicals to process, costs about a pound. Probably someone will argue that point. Maths isn't my strong point! But I am talking about readyloads which are double the cost of sheet film. I may therefore have a look at getting some DDS's and loading myself.

Tonight I feel very satisfied. It was fun, no stress this time. Dare I say it I am happy!

I wish I'd taken up large format years ago, especially since I went to New England last fall. I think of the velvia chromes I may have come away with!

Thanks to everyone once again.

Steve

I have to say that those HP tanks are just some of best tools I have found so far. But not without some problems in my learning curve. I had several bad experiences* with just one simple reason - I didn't read the manual... (like - who needs the manual to develop some b&w film? nonsense... not? not. :))
I have bought two of them and after two months I have ordered two more, and now I can "batch process" a lot of film. sort of dip and dunk method. I'm starting with clear water to prepare my film (efke emulsion) in 1st tank, second one is for developer and then one for acid stop bath or for water development (depends on work I'm doing), and the last one for fixer. So I have 4 sets of hangers and can develop 24 sheets in one session (I have tried to put 12 in a raw but film sticked together and I didn't like the process of separating them apart).
Sure, sometimes I'm developing just one set of film, and than I work as someone described earlier - slow and gentle agitation with counting twice 30 seconds for pouring chemicals in and out. works fine for me.
(*bad experiences? heh - the first set of negatives just didn't wont to stay in position... WHY? I screamed... well, stupid you - even flute in hangers is for glass plates. than, the problem with pouring chemicals in... or out. what a SLOOOOOOW process..! until you unscrew both caps for some 60-90 degrees... Sheets are floating in the tank? FLOATING? and they are coming out well sandwiched together... why do I have that little orange holder with bunch of teeth on it? yup. Read This F(ine) Manual... :))

To pour and drain chemistry quickly, turn the tank on its (narrow) side so that both the bottom drain valve and the valve on the lid are "up" - if you then open the lid valve and pour chemistry through the BOTTOM valve, you will have an air escape which makes the process much quicker!