Brief Description of the Tank/Drum Systems

Developing film or photographic paper requires either a manual or an automatic processor—such as my DIY FPP-3 or commercially available options like the CPE-2 or ATL-3—as well as several development drums tailored to specific needs. There are multiple drum systems available (e.g., Paterson, Jobo, etc.). In this short post, I focus exclusively on JOBO drums, which in my opinion are the best choice for rotary development due to their modularity, flexibility, and proven reliability.

Over the decades, JOBO has developed several drum series. The 1500 series was intended primarily for hobbyists and supports 110, 135, 120, or 220 film rolls, suitable for inversion or rotary processing. The 2500 series, on the other hand, was designed for professional use, capable of handling roll film and sheet film up to 4×5 inches. These drums are not meant for traditional inversion development. The 2800 series was designed specifically for daylight processing of prints, whether used with or without a JOBO processor. Lastly, the 3000 Expert Drum series was engineered for the highest-quality rotary processing of sheet film (4×5” and larger).

All JOBO drums follow a numbering system that ends in 0, 1, or 3, indicating their drive mechanism:

• 0: no magnet
• 1: magnet attachment
• 3: cogwheel

The magnet or cogwheel enables 2500 and 2800 drums to interface with automatic processors that use either a magnet-drive or a lift system. Cog-driven drums are compatible with JOBO autolabs and processors like the CPA-2 and CPP-2.

For my FPP-3 processor, the 2500 and 2800 series drums with magnet attachments are ideal (see the FPP-3 blog for details). Unfortunately, the 2800 series is no longer in production, but these drums are often available on the second-hand market—and occasionally as new-old stock if you’re lucky. Due to the discontinuation of the 2800 series and the rebranding of the 2500 series as “Multitanks”, finding reliable information about the chemical capacities of various drums can be tricky—especially if you’re repurposing a print drum for film development. I’ve successfully used 2800 print drums with the 2509n film reel and achieved excellent results, provided the correct chemical volumes are used.

A key resource that helped me compile accurate data is The Rotary Processor Manual by John Tinsley (sadly out of print), along with several online references. The chemistry volumes I use are for one-shot processing, with no reclaiming. Importantly, the torque limitations mentioned in JOBO-USA manuals (relevant to the CPE-2, CPA-2, CPP-2, ATL-1/2/2-Plus) do not apply to my FPP-3 processor, which features a more robust motor. Much of the information on adapting print drums for film development was found on the Large Format Photography Forum.

I hope this post proves helpful for other photographers exploring the JOBO system.