4x5 vertical tank

[John Cahill]

Another neophyte question. I have never liked developing sheet film in trays. But the tanks I have acquired take about half a gallon of chemistry. Has anyone heard of a way of using something, or making a suitable "mini" tank--kind of the size and shape of a slice of bread-- which would hold about eight ounces of developer for souping a sheet of film or, maybe two, on stainless steel holders? Rube Goldberg, are you still out there?

[Ron Marshall]

John, you might do something similar to what this person has done, but a bit slimmer:

http://davidhoulder.com/info/4x5tanks.html

[Scott Kathe]

Hi John,

I'm just starting out myself but you could invest in the BTZS tubes or make your own. I haven't done this because I haven't had a problem with tray developing yet. That may change though because I did get bored with the last set of negatives I developed. I'm sure listening to some music would help me out I've also used the 'taco' method and a Paterson 4 tank with some sucess.

[John Cahill]

Ron and Scott,
Thanks, Ron for that link. I should think that would work fine for me. I did not know that PVC is available in sheets. As I am headed for Home Depot and Lowe's this afternoon, I shall see what I can acquire.
Scott--what is the taco method with a patterson tank?

[Ted Harris]

The HP Combiplan is the closest thing I know of to do what you want. You will find lots of threads disussing it on the Forum. Look at it here http://www.bhphotovideo.com/bnh/cont...list&sku=23845

[Jerzy Pawlowski]

I second HP Combiplan. You can try to get it from Jim at MidWest Photo Exchange. At least it was cheaper than from other stores about half a year ago.

[Bruce Watson]

Another neophyte question. I have never liked developing sheet film in trays. But the tanks I have acquired take about half a gallon of chemistry. Has anyone heard of a way of using something, or making a suitable "mini" tank--kind of the size and shape of a slice of bread-- which would hold about eight ounces of developer for souping a sheet of film or, maybe two, on stainless steel holders? Rube Goldberg, are you still out there?

The most efficient in terms of chemistry volume is probably the Jobo 3xxx tanks. The minimum volume for a 3010 (10 sheets of 5x4) is around 270ml IIRC.

If you are using more dilute developers, you might find something like the old Nikor variable size stainless tank usefull. It can do 12 sheets of film in something over a liter IIRC.

I suspect that you can't find a really thin dip-'n-dunk tank because it would have been hard to make such a thing back in the period following WWII, which is the last big period of R&D for this sort of thing. It would actually be rather expensive to make it today, and the lack of demand would make it very unlikely that one could recover the tooling costs, much less make a profit. But I'm just guessing here...

[Richard Sanders]

Doesn't Bruce Wehman have a design for a vertical daylight tank?
http://www.wehmancamera.com/tank.htm

If you scaled that down to 5x4 it should be fairly economical.

[Louie Powell]

John -

There aren't a lot of options for new equipment, and what you will find in the used equipment market is a real gamble. So lets assume that the starting position is the solution must be home made.

It's relatively easy to find 1/4" plexiglass at places like Home Despot. You can also find, thinner material, but it also is more flexible, and that may not be ideal for a film tank. So let's assume that the tank and rack are made of 1/4" plexiglass.

What that means is that the rack for the film will be at least 1/2" larger than the outside dimensions of the film - 5.5 x 4.5 inches, or 24.75 square inches. Without actually designing a rack, an intuitive expectation is that a 1 inch rack could hold three sheets spaced 1/4 inch apart. And the rack would require at least 1/8 inch clearance on all sides to be easily inserted into the tank. So that means that the inside dimensions of the tank would have to be 5.75 x 4.75 x 1.25 inches. That translates to a liquid volume of the tank of 34.14 cubic inches, or 559.5 ml, minus the displacement of the rack and film. Again, without a rack design, we can't determine the displacement, but let's just assume that it will take 400ml of liquid to fill the tank with a full rack in place.

I use a slosher to process 4x5 film in open trays, and I can process six sheets at a time in 800ml of HC110, dilution H. That turns out to be exactly the same amount of chemical that the hypothetical home-built tank would require for the same amount of film. I know that I can get even development with my slosher and tray, but I don't know about the home-built tank. The tank would be a lot of work to make, and frankly, the rack would be a complicated design.

Bottom line, I would stick with the slosher and tray.

[vinny]

I made 3 tanks for 8x10 sheets a couple weekends ago out of 1/4" plexi from home depot. It's not actually 1/4 by the way, it's a bit thinner. I cut all the pieces ahead of time and used a hot glue gun to put them together after the aquarium adhesive the hardware store guy gave me didn't hold up. 3 tanks for 8x10 cost me about $40 for the plexi. Each tank will hold 5 sheets and uses 5200ml of chem's.Don't press the pieces to tightly together or you'll push all the glue out and get leaky tanks.
I processed 35 sheets of 8x10 last weekend without a problem. I plan to make a skinny tank set for doing 1 or 2 sheets at a time.
vinny

The 1/4 abs that appears on Bruce's site looks like the same stuff we use in the movie biz for "dance floor" that they push the camera dolly on. It's about $90 for a 4'x8' sheet and it's very sturdy, smooth on one side and textured on the other. I considered that material but didn't have anywhere to store that much of it.