View Full Version : Motor Base Developing Question

zero megapixel
13-Sep-2014, 14:36
I'm a newbie to 4x5 so please forgive my lack of knowledge....

I've developed 120 many times by hand agitation but I have a Beseler Motor Base on the way that I plan to use for 4x5 as well but my question is, do you use the same amount of developer meaning filling the volume of the tank.

I've Googled around but cant really find any definitive information accept for 10 to 15 percent in reduction times.

13-Sep-2014, 14:41
I use a Beseler 8x10 print drum on a motor base for up to four sheets of 4x5 and use 200ml of chemistry.

13-Sep-2014, 14:47
I forgot to add that I don't reduce developing times. I use the same times that I do for inversion tanks.

zero megapixel
13-Sep-2014, 14:58
I use a Beseler 8x10 print drum on a motor base for up to four sheets of 4x5 and use 200ml of chemistry.

I forgot to add that I don't reduce developing times. I use the same times that I do for inversion tanks.

I also forgot to add.... :eek:
I'll be using a 1000ml Paterson tank and trying the taco method first on the base so lets say 500ml of developer would be fine?

13-Sep-2014, 15:31
That is a bad idea I think.. I'm not 100% sure on this but I don't believe the taco method lends itself to rotary processing as developer will not flow over the negatives in the normal fashion, rather it will flood around the ends of the tacos... As a guide, using a jobo 2520 tank developing six 4x5 sheets at once, if I'm doing hand inversion I require 1500ml of developer, if I'm doing rotary developing I only require 270ml of fluid. with the taco method I would assume you would halve the normal amount of developer but watch it to make sure the lid doesn't leak. also, keep in mind that when it rotates, the taco'd sheet at the top (out of the developer solution) may still have portions of its outer most edges in the developer which will cause overdevelopment in those areas, and it also may retain developer where the two edges of the sheet meet in the taco, causing uneven results also..

John Kasaian
14-Sep-2014, 07:49
Yep, tacos are for lunch, not rotary development.
Get the proper drum and give your film a fighting chance.

Jim Noel
14-Sep-2014, 09:58
I totally agree with Alex and John

Eric Woodbury
14-Sep-2014, 13:22
This isn't rotary tank, but an interesting article by David Kachel about tubes in trays. Worth the read.


I used a rotary base for years, but gave it up for tubes for my 5x7 and 4x5. They are ABS with caps, so they are daylight. As David points out, maybe that doesn't matter and I'd be just as happy with tubes in tray in dark.

14-Sep-2014, 13:33
I agree with the above that combining the taco method and rotary processing would be a bad idea. I would think the liquid movement would push the negatives around inside the tank and cause all sorts of problems. In my drums, the negatives lay flat against the sides so the chemicals can flow over them easily.

al olson
14-Sep-2014, 16:42
I have been using the RA-4 process since around 1977. In the beginning I was using the Beseler processor drums with the motor base agitator. A drawback with this method is that there is no temperature control so that the chemical temperatures decrease throughout the procedure. Also, the use of tubes means that they must have been thoroughly rinsed and wiped dry, otherwise a drop of water rolling across the paper will leave a streak as development begins.

About 20 years ago I procured both a used Jobo as well as a DoMac roller processor from Adorama for around $1800. The Jobo tubes have the same difficulty is the Beseler tubes for the reason that they must be completely dry before use. The process can be sped up by using multiple tubes to allow the recently used tubes additional air drying time after wiping. For this reason, I use the Jobo for prints when I only plan to make a few. But using one shot chemicals gets expensive.

When I am doing a print session where I plan to make a large number of prints, especially when printing multiple copies of the same negative, I prefer the DoMac. The DoMac is a very simple design with two heated troughs, one for the developer and the other for the blix. Each trough contains a liter of the chemicals.

The temperature is not adjustable, although it can be calibrated for a single temperature via an adjustment on the circuit board. It can also be used at room temperature for B&W. Because the precision rollers squeegee the print as it comes out of the developer there is no need for a stop bath when using it for B&W.

I don't know if you can find a good used DoMac on ebay or craigslist. The manufacturer is a precision roller company that produced these processors for a number of years. Mine has 17" rollers for processing 16" wide paper. There is also a 21" model. The manufacturer still has parts and told me recently that they still assemble a processor on special order. I can provide contact information if you are interested.

zero megapixel
27-Sep-2014, 12:25
I listened to everyone and before I make a mistake, I was able to buy a Unicolor 8x10 drum off eBay.