View Full Version : 4x5 Daylight Processing Film Tank

Robert Ruderman
28-Jul-1998, 11:20

I'm looking for recommendations for a daylight processing film tank for 4x5 nega tives. At the moment, I am (and have been) using a Combi-T film tank, but have found that the tank can (and does) damage the film emulsion during processing. So, it's time to try something else.

Thanks, Robert

John Lehman
28-Jul-1998, 18:01
I started using a Jobo 2500 series tank and reel for sheet film a couple of months ago, and liked it so well I ordered the larger tank and extra 4x5 and 2x3 reels. Depending on which tank you use, it does either 6 sheets of either size film or 12 of 4x5 and 18 of 2x3 at a time. I use it for inversion processing with PMK. By using different reels for different exposures (and keeping the unused ones in a lightproof box until needed), I have even been doing N-, N, and N+ sheets in the same batch. It makes sheet film almost as easy to use as roll film.

On the other hand, the Yankee tank is perfect for producing uneven development streaks, or for film washing.

Tim Kimbler
29-Jul-1998, 23:32
I have the same JOBO tank. I bought it used at a camera show. I use a Beseler rotary motor drive, also bought used. All though I am new to 4X5 I have had per fect results. Total cost was 100 dollars. I use 16oz of developer for 12 sheet s of film.


Henry Stanley
30-Jul-1998, 00:51
<<I have the same JOBO tank. I bought it used at a camera show. I use a Beseler rotary motor driv>>

Can anyone tell me if I can use JOBO tanks with a used Unicolor rotary motor dri ve (instead of JOBO or a Beseler)?

Any tips on using the Beseler or unicolor motor units?

When switching from Yankee tanks, etc., is there any modification in developing times for continuous drum processing?


Lukas Werth
5-Aug-1998, 19:17
Well, I use the Combi tank since some years, and I also kept having problems wit h emulsion damages at the beginning. But I still use it today, and am now quite happy with it. According to my experience, the film first has to be carefully lo aded (the loading help they supply with the tank is useless); you have to feel i f the loaded sheets are correctly spaced - at the bottom as well as at the top. Then, a lot depends on the right moving rhythm. Don't move too forcefully, do no t jerk the tank, or otherwise a sheet may slip out of its slots. Just turn it sm oothly.

The tank is very good to develope with diluted emulsions for lower contrast, bec ause you can turn the tank only every 30 seconds or even every minutes. I now de velop with pyro; it works perfect. I just pour the developer into the tank, clos e the lid, and place it along with a plastic water container into a carton insid e my changing room 8from Calumet). The carton is cut out to keep the tank and th e water container vertical. Then I fill the negs into the holder, water them for 1 minute, put the holder into the tank, moving them up and down five or six tim es. Having placed them this way gives me enough time to close the lid, get the t ank out of the changing room and begin turning it.

The advantage: when developing, I am able to read something or watch TV. With py ro, I have not lost a single negative yet

Sean Billy Bob Boy yates
4-Dec-1998, 01:42

I process my sheet film, all formats, B&W, in either Unicolor or Besseler daylight color print tanks with a Besseler or Unicolor motor base. I have not paid more than $20.00 or so per drum and refuse to pay more than $30.00 for an electric motor, which is what the motor base is after all. I don't understand how the catalog houses can expect to pay $125.00 for those things.

That rant over, I'm quite happy with this poor man's JOBO, I wish I had the temperature control during processing, but I don't, so in the winter I keep my processing times short. It's also a lot more economical on chemistry than the Yankees and other brand tanks too, 75 to 100 ml/8 X 10 surface area/chemical.