20x24 drum, anybody have any experience with film?

[epatsellis]

Having recently gone the route of rotary processing, and building a 20x24 camera, film processing is my biggest concern. Anybody use the larger Ciba or Unicolor/Beseler drums with really big film? The 8x10 Beseler I have works wonderfully, can I expect the same level of processing nirvana, or will I be making a larger roller base to keep 20" of tube from walking itself off the base?



erie

 

[Konical]

Good Evening, Erie,

I'm a fan of rotary film processing, albeit only in 4 x5. I can't think of a simpler, more efficient method, unless you're into stand or water-bath development. I've used drums up to 16 x 20 size for print development; a large 16 x 20 drum is somewhat awkward on the typical motor base, so I don't know how well a 20 x 24 drum would work out.

One alternative is to rotate manually. I have a large home-made drum about 48" long which I have used for processing mural-size paper. I built a "rotator" by mounting four furniture casters upside down on a sheet of plywood. No motor power, but it works like a charm. A somewhat down-sized version should serve for 20 x 24 drum.

Konical

 

[Paul Howell]

Did ,or does, anyone make a 20X24 20X24 drum?

 

[Lopaka]

JOBO 3063 is a 20x24 drum (designed for prints). Quite expensive it was. I do have one I use for Ilfochrome prints.

Bob

 

[Jim Noel]

The 3063 is not a good drum for film. It is built with two breaks in the ribs and streaks are inevitable in these areas. I used them for a while, but soon began to notice the streaks. According to another thread, others have had similar results.

 

[sanking]

Having recently gone the route of rotary processing, and building a 20x24 camera, film processing is my biggest concern. Anybody use the larger Ciba or Unicolor/Beseler drums with really big film? The 8x10 Beseler I have works wonderfully, can I expect the same level of processing nirvana, or will I be making a larger roller base to keep 20" of tube from walking itself off the base?



erie

I have a couple of 20X24" drums, one by Doran Enterprises and the other by Simmard. Not sure if Unicolor or Beseler made 20X24" drums, but I have never seen one.


Sandy King

 

[dmax]

Erie,
Ciba used to sell a 20x24 drum, but it's designed for prints. I've had no problems processing regular film in either Beseler or Unicolor print drums up to 11x4 in size, despite the internal ribbing designed into the tubes that permit better movement of chemistry and to prevent the print from sticking to the sides. But reversal processing is another story. As Jim points out, the internal ribs or join lines of the drum leave lines on the base side of the film whenever I process. And as Konical has said, even a 16x20 drum sits awkwardly on a motor base and needs quite a bit of minding. More so with a longer drum. To make sure that the 20x24 Ciba drum stayed in place, we had to cobble together a pair of Y-shaped roller supports (with a freely-rotating wheel on each arm) which we placed at either end of the drum to provide additional stability. Not very elegant, but considering the cost of Cibachrome chemistry and paper, the arrangement worked rather well.

A home-made tube may work, but I'd be concerned with the film sticking to the sided of the tube and the inability of chemisty to reach the back side of the film. Like the emulsion side, the base side of film does require full immersion for complete processing.