Stark SST4 film processor

[Steven Lee]

I have upgraded from the JOBO CPE to the Stark SST4 film processor. This was a leap of faith because there's very little information about these machines on the Internet. Wanted to drop a few notes for those who may be interested.

The advantages:

1. The primary reason for the upgrade was more accurate and sophisticated temperature control. The near-useless water bath has always been my gripe with the CPE. Instead of the crude knobs, the Stark uses an electronic display similar to bigger JOBOs with 0.1C granularity. Accuracy matches granularity too, as verified by my certified thermometer. The manual says that the heater turns on after the temperature drops below 0.2 of target. Additionally, there's a water pump which constantly re-circulates water in the bath achieving 100% uniform temperature.
2. Build quality is also somewhat better. JOBO's shaky plastic feel somehow never reconciled with the "made in Germany" sticker in my head.
3. More compact than a JOBO which matters for my small laundry room.

Other thoughts

The machine works with all types of tanks. This is great for the manufacturer so they can serve a bigger market with a single model, but it doesn't work as well as a fully integrated system like a JOBO which firmly holds a tank in place. Instead, SST4 allows you to place a tank anywhere you want by adjusting the placement of roller wheels. All tanks tend to drift during agitation somewhat but regular-sized JOBO tanks like 1520 are nose/top heavy which accelerates this drift. You are supposed to configure one of the wheels to be a stopper, but because it's on one side (one of the rods) its stopping action isn't smooth and a tank wobbles during rotation. I doubt it has any effect on the end results, but makes the overall operation less refined. It works much better with Patterson tanks or longer 1540 JOBOs because they are better balanced.

The SST4 does not have the ability to heat chemistry. There's a bigger brother called SST5 which can. In my case I did not need this feature because I've always preferred using a regular basket with 110-120F water, this saves a lot of time and makes the processor more compact.

My unit is a US model with a corresponding power supply, according to the manual. Yet it came with the euro power cord, perhaps by mistake. It is a standard power cord though, the same kind used by PCs and computer monitors. I had several laying around.

I see it as something in the middle between "junior" JOBOs and the bigger CPP models with electronic temperature control. I wasn't happy with the former and couldn't afford the latter, so it made sense.

TLDR: recommended.

 

[mshchem]

How much? Where did you purchase?

 

[Steven Lee]

@mshchem

CatLABS

Large format cameras, lenses, film holders, darkroom equipment, Jobo sales and service. We carry large format cameras and lenses, Jobo machines,...

www.catlabs.info

 

[mshchem]

@mshchem

CatLABS

Large format cameras, lenses, film holders, darkroom equipment, Jobo sales and service. We carry large format cameras and lenses, Jobo machines,...

www.catlabs.info

I remember seeing this sometime back. Looks like a great, sturdy machine. Nice size. Do you plan on trying any other brands of tanks, or 2500 series Jobo?

 

[Steven Lee]

@mshchem Any cylindrical object will work, the issue isn't the manufacturer but the tank's length. Any long-ish tank holding two or more reels will work fine, but shorter ones will be less stable and wobble a bit. My primary tank is the 1540 JOBO which works beautify.

Here's a video showing it with several tank types:

 

[AgX]

@mshchem Any long-ish tank holding two or more reels will work fine, but shorter ones will be less stable and wobble a bit.

How come?

At least the position of the guide rollers can be adjusted, by means of shifting those O-rings holding those rollers in place.
But wat about the driving rollers? Are they pressed onto the driving axles or fixed by set screws?

There also is seemingly a rear guiding roller (end-stop) on the driving axle, its seemingly front counterpart though is misplaced for this function. Maybe they are just intended as inertia masses.

 

[AgX]

I could not find out the manufacturer. The processor is seemingly anonymously made only for retail by Catlabs and Fotoimpex. However Fotoimpex offer two versions of the SST 4, a shorter and a longer version, the one shown sample though is technically different from what Catlabs show!

STARK Rotation Processor SST4 (long version for drums up to 58 cm) - fotoimpex.com analogue photography

Rotation Processor with electronically controlled tempering bath for all traditional lm & paper processing The SST4 Processor is universally compatible with most existing ...

www.fotoimpex.com

 

[Steven Lee]

@AgX shorter JOBO tanks are too "nose heavy". When they lay on a side they simply tip forward off the rollers. If you have something like 2551 try laying it down on the edge of a table and see what happens. The manual says it's made by EDV Technik Stark GmbH, Gummersbach, Germany.

 

[AgX]

Thank you for both informations.

Concerning the "too" short tanks, one might stick a flat weight to their bottom, shifting center of gravity, but the same time keeping it straight and stable when using it upright for filling.

 

[AgX]

But what about the driving rollers? Are they pressed onto the driving axles or fixed by set screws?

There also is seemingly a rear guiding roller (end-stop) on the driving axle, its seemingly front counterpart though is misplaced for this function. Maybe they are just intended as inertia masses.

At enlarging the photo it becomes clear:

-) the driving rollers are fixed in place by a set-screw, thus can be adjusted in position
-) the wheel at the end is held in place by O-rings, as the guide rollers, and thus can be adjusted in position too.
It thus is a plain end-stop, as first thought.

 

[Steven Lee]

@AgX you are right. The most obvious weight for sticking to the bottom of a JOBO tank is their magnet if you have one. But this IMO is almost an edge case: why would someone want to use a single-reel tank in a processor? This has additional minimum chemical volume implications. Dual-reel tanks aren't just more stable, they also hold more chemistry which is something you want because JOBO minimums printed on their tanks are ridiculous.

 

[AgX]

The SST4 does not have the ability to heat chemistry. There's a bigger brother called SST5 which can. In my case I did not need this feature because I've always preferred using a regular basket with 110-120F water, this saves a lot of time and makes the processor more compact.

This is puzzling.
As both Catlabs and Fotoimpex state that the SST 4 has a tempered water bath. Something which of course needs some heating element. And your yourself have it about a heating element and a pump.

It could be that such element is too weak to heat up water from let's say 10°C to 40°C in a reasonable time, so that one should fill it with water somewhat preheated somewhere else. But then to offer also a model that can heat up from the start only makes sense with the idea in mind to offer a second model with a large price gap.
But neither at Catlabs nor Fotoimpex I see a model 5 described.

 

[Steven Lee]

@AgX yes the SST4 has a beautify controlled tempered water bath. It will keep your tank at temperature, but I does not have any room for your chemistry bottles. See the video above. SST5 shown below does:

 

[AgX]

Where do we find the information about this tank?

The Catlabs page you linked to has it in its title about both models, 4 and 5, but only describes model 4 ...
And that does not take any bottles.

 

[AgX]

@AgX Why would someone want to use a single-reel tank in a processor? This has additional minimum chemical volume implications. Dual-reel tanks aren't just more stable, they also hold more chemistry which is something you want because JOBO minimums printed on their tanks are ridiculous.

Per reel all the double or multi-tanks from Jobo yield less minimum (advised) bath volume than their single tank.

Additional bath volume per reel one would achieve by leaving out reels as you advise.
But this to me is uneconomic use of such tanks.

As in the Stark processor a standard tank, thus with a cap, can be used, it to me instead makes more sense to install all reels, loaded with film, but also fill more bath than advised, with still keeping a distinct fluid level.

 

[Steven Lee]

@AgX that's the thing - there isn't much about these machines on the Internet, that's why I started this thread. It's a shame because they are a valid alternative to a JOBO, but with their own quirks. I simply emailed them and they sent me the product manual.

Here's the link for SST5 manual. The SST4 is similar.

Regarding chemical volume: I often found JOBO minimums to contradict datasheet minimums for various chemicals and have learned to ignore them. It's too easy to underdevelop your film if you follow the JOBO minimums and practice loading two 120 rolls on a single JOBO reel.

 

[AgX]

Well, Fotoimpex does not offer the model 5, so there is no blame on this.
But that Catlabs page is weird, and we already had it about their marketing at another thread.



"You shouldn't be running two 120 rolls in a single-reel 1520 tank with JOBO-recommended 240ml of C41 developer, for example. Which means that for most practical purposes it's best to use 2-reel tanks and they ride comfortably in the SST4."


By not loading 2 type 120 films onto 1 reel, in a 1520 tank but spreading them over 2 reels you do not change anything of the bath volume of 240ml, and thus nothing on the bath volume per reel. What you instead do is putting both films at same central position on the reel, and not one central and one peripheral.

But this does not affect what I wrote above on bath volumes.

 

[Steven Lee]

@AgX we're speaking past each other on volume management, but it's a boring tangent here so let's just leave it behind

 

[MattKing]

Regarding chemical volume: I often found JOBO minimums to contradict datasheet minimums for various chemicals and have learned to ignore them. It's too easy to underdevelop your film if you follow the JOBO minimums and practice loading two 120 rolls on a single JOBO reel.

It is always important to remember the volume indications on any type of tank only tell you how much liquid is necessary to properly immerse or otherwise physically deal with the film.
Those volumes don't tell you anything about the chemical capacity of the particular developer or other chemical you choose to use. You get that information from the information about the chemical. With black and white film developers, as an example, some have excess capacity at the minimum volumes indicated on the tank, while others require you to increase the solution volume to do the whole job.

 

[AgX]

I just realized that the URL of that Catlsabs store even hints at a model 8 of that Stark processor, or even at a range of models 4 to 8 ("SST4-SST8").

 

[ic-racer]

The primary reason for the upgrade was more accurate and sophisticated temperature control. The near-useless water bath has always been my gripe with the CPE. Instead of the crude knobs, the Stark uses an electronic display similar to bigger JOBOs with 0.1C

I have never used a CPE but does it not have a circulating pump? I have the TB-12 tempering bath with no pump, and it keeps the temp constant by water convection; no pump needed.

 

[AgX]

I have never used a CPE but does it not have a circulating pump?

None of the CPE models had a circulating pump.

 

[AgX]

Concerning the Stark processors:
I would have designed the electrical system differently, for electrical safety reasons.

 

[Steven Lee]

@AgX did you obtain their schematics somewhere? I'm not sure you can see much from a picture.

 

[AgX]

I have not got the schematics, I am talking just about what I see at those product photos.