Paterson, Jobo, Stearman Press: Choosing the Right Developing Tank When Results Actually Matter

The developing tank is the heart of the home darkroom. Not the developer, not the fixer, not even the thermometer. The tank. It determines how chemistry contacts the film, how agitation works, and to a large extent how consistent your results are going to be. Yet most beginner guides brush past the subject in two paragraphs with a vague recommendation to buy "a Paterson." That's not wrong exactly, but it leaves a lot unsaid.

If you've been developing for a while and you're wondering whether your current tank is holding you back, or you're looking to move into medium format, 4x5, or just a more systematic and repeatable workflow, this is the article for you. We're going to look at three systems that turn up in most serious home darkrooms: the Paterson Super System 4, the Jobo 1500, and the Stearman Press SP-445. Three different approaches, three distinct user profiles.

The Paterson Super System 4: The Default Choice, and For Good Reason

The Paterson system has been around for decades and has outlasted generations of home processors. The Super System 4, molded in high-impact polystyrene, is lightweight, easy to clean, and handles both 35mm and 120. The auto-load reels are its main selling point: drop the film leader onto the guides, alternate the two halves of the reel back and forth, and the film walks itself inward. In theory.

In practice, it works very well with a supple, cleanly rewound 35mm roll. With 120, especially film that's slightly damp or has curled a bit after respooling, loading can turn into a fight. The flex in Paterson reels, which is part of what makes them guide film so well, becomes a liability when the film pushes back. A few practice runs in daylight with a sacrificial roll teaches you the feel of it. After that, it generally goes in without a battle.

Inversion agitation is straightforward and effective. The central agitation rod that comes with the tank is mainly useful for dislodging air bells at the start of development. Some people ignore it entirely, others swear by it. For those first few seconds it does help, hard to argue otherwise. After that, regular inversions are all you need.

Where the Paterson shows its limits is consistency. With well-executed inversion technique the results are solid, but inversion introduces a human variable that rotary processing eliminates: the regularity of your rhythm, the way you flip and return the tank, the timing between sequences. Continuous rotary agitation carries its own risk, specifically over-even agitation at a constant speed in one direction, which can produce streaking. For most purposes the human variation in inversion is negligible. For someone trying to replicate a result precisely from one roll to the next, it's worth factoring in.

The big advantage of the Paterson is its ecosystem. Reels are everywhere, replacement parts are easy to find, and the learning curve is short. If you're developing a roll or two a week and you're happy with the results, there's no particular reason to switch.

The Jobo 1500: When Consistency Becomes the Priority

The Jobo 1500 is often pitched as a Paterson alternative, but it's closer to a change in philosophy than a straight upgrade. Jobo tanks were designed from the start to work equally well with manual inversion or motorized rotation, and that dual-purpose thinking shows in how they're built.

Jobo reels (model 1501) are rigid, in a denser plastic than Paterson uses. Loading works differently: you feed the film in from the edge, into a channel, and slide it around the full circumference of the reel. The technique takes some getting used to. Compared to Paterson reels, Jobo reels are a pleasure once you have the method down. Heavily curled film is always a challenge on any system, but in practice you tend to have better odds with the Jobo than with most other brands. For 120, especially with thicker or awkward emulsions, a lot of people find the Jobo more reliable once it clicks.

The Jobo CPP-3 processor offers repeatable, high-quality film processing through its proven rotary system, with automatic agitation, automatic temperature control, one-shot processing capability, and accurate development time control. In rotary mode the tank rotates continuously on its axis, keeping chemistry moving constantly across the film surface. Development uniformity is clearly better than manual inversion, with no human variability to account for.

The Jobo 1520 UniTank holds two 35mm reels or one 120 reel and requires 485ml of chemistry for inversion, or just 240ml in motorized rotary mode. That's a meaningful saving when you're running expensive one-shot developers.

Without a Jobo processor, the tank runs as an inversion tank much like a Paterson, with the same demands on your technique. Investing in a processor (which holds its value well on the used market) genuinely changes what the system can do, but that's a different budget conversation. Worth noting: Jobo CPE-2 processors periodically reverse the direction of rotation to prevent directional streaking, which makes them more robust than simple single-direction rotation.

The Stearman Press SP-445: A Specific Niche, Perfectly Filled

The SP-445 isn't a conventional developing tank. It's a compact system built specifically for 4x5 sheet film. Timothy Gilbert, an American engineer and photographer, designed it to give large format shooters an efficient, economical, and practical processing solution.

The concept is clean and well thought out. Up to four 4x5 sheets slot into plastic film holders, the holders stack inside the body, and the whole thing seals watertight. You can then add chemistry in full room light. The required volume is around 480ml for up to four sheets, which is genuinely economical for large format compared to traditional open trays.

The SP-445 is straightforward to use and fairly elegant in its design, though the film does need to be loaded into the holders in complete darkness before chemistry goes in. Agitation is done by inverting the whole unit, with a 180-degree rotation between each inversion to break up uniform agitation patterns. Uniformity is generally very good, as long as you follow the protocol consistently.

The limitations are clear. The SP-445 only does 4x5. It's not a system for 35mm or 120, full stop. And like any compact sealed system, loading requires complete darkness, which adds a step compared to daylight tanks. The price is also in a different range from standard plastic tanks, typically around $70 to $90 USD.

For someone shooting large format and processing a handful of sheets a week on their kitchen counter, it's the most practical solution on the market. For everyone else, it simply doesn't answer the question.

Comparing the Three: Some Practical Criteria

Development uniformity. Motorized rotary processing on the Jobo gives the most repeatable results. The SP-445 with strict inversion protocol comes close for 4x5. The Paterson with well-controlled inversion technique is entirely sufficient for the vast majority of work.

Film loading. The Paterson auto-load is usually the most intuitive starting point. The Jobo requires a different technique that becomes second nature with practice. The SP-445 requires complete darkness for sheet loading, with no auto-load mechanism.

Chemistry volume. The Jobo in motorized rotary mode is the most economical (around 240ml for two rolls). The Paterson needs more. The SP-445 sits at 480ml for four 4x5 sheets, which is very reasonable for that format.

Format compatibility. Both the Paterson and Jobo cover 35mm and 120. The SP-445 is exclusively for 4x5.

Durability. All three systems are known for holding up well with proper care. Paterson reels can warp slightly if you force film in or expose them to aggressive chemistry without a quick rinse afterward. Jobo reels, being more rigid, tend to hold up better over the long term.

Entry cost. A Paterson Super System 4 with two reels runs around $40 to $60 depending on where you buy it. A Jobo 1520 kit is often in a similar range. The SP-445 costs more for what it does, but it fills a role that nothing else handles as well.

So Which One Should You Get?

The Paterson is still the best starting point for 35mm and 120 if you're developing regularly but not chasing measurable reproducibility. It's available everywhere, parts are easy to find, and inversion technique is something the whole community knows inside and out.

If you want to step up consistency without necessarily committing to a motorized processor, the Jobo 1500 is worth the switch, especially if you're thinking about adding a CPP-2 or CPP-3 down the line. The system is modular, so nothing gets wasted as you build it out.

If you're shooting 4x5 and want a clean, economical processing system that doesn't require a dedicated darkroom, the SP-445 is hard to beat. It's a niche product, but it owns that niche completely.

Going Further

If you want to go deeper on agitation and how it affects development, the Ilford technical data sheets (particularly those for ID-11 and Ilfosol 3) lay out recommended inversion protocols by format and dilution. That's a good place to start calibrating your technique before looking at more sophisticated equipment.

For anyone considering rotary processing, the Jobo 1500 Series remains the most thoroughly documented system and the easiest to find used, often sold as a lot with a CPE-2. Checking the condition of the processor seals is the first thing to do before buying.

The Stearman Press SP-445 is available directly through their site or from specialist retailers like B&H Photo. If you're just getting into large format, budget for a good changing bag while you're at it. It's one purchase you'll never regret.

Sources

• store.bandccamera.com — Paterson Super System 4
• bhphotovideo.com — Paterson 35mm Tank
• bhphotovideo.com — Jobo 1520 Two Reel Film Tank
• glazerscamera.com — Jobo UniTank 1500
• bhphotovideo.com — Stearman Press SP-445
• viewcameraaustralia.org — Review: SP-445 Compact Developing Tank
• emulsive.org — Gear Review: SP-445 4×5 Film Processing System
• talkphotography.co.uk — Paterson or Jobo for film developing?
• rangefinderforum.com — The effect of different methods of agitation