That's it! I'm designing and building my own film processor.

[michaelbsc]

Both the phototherm and the Jobo like processor require expensive tanks.
The truly affordable system would use Paterson tanks.

 

[EdSawyer]

I don't know... we'll have to just agree to disagree. I think only a few things favor the DIY approach. Mostly cost and availability, if that.

You still have to rely on 3rd parties for parts. (not like you are fabbing them all yourself from raw materials in your backyard... ;-)

Cost: variable as parts suppliers are free to raise/lower prices.

Standardized: only so much as the parts are still available from more than one source.

In favor of DIY: yes, you can find parts whenever/wherever you want, vs waiting for a phototherm to show up on ebay. But it still might take just as long, when you factor in the fabrication/build time and working out bugs.

The upside of the phototherm, et al., is that they already did the hard part: all the engineering, QA, UL certification, and building the damn thing. No assembly required, really. It uses standard patterson reels so that's a plus too.

I am into DIY in general so I applaud the effort. Plus I got lucky and found a nice phototherm on ebay for a reasonable price.

Bottom line: I'd rather just be spending my time processing film than fiddling around building a processor to do so. And my time is worth enough that it's cheaper in the long run to just buy the phototherm than it is to spend the time to build a processor.

To each his own though! The upside is that people are still processing film in general and that's a good sign. ;-)

-Ed

If we have to (a) be lucky enough to find one on Ebay for an agreeable price ($300-$800), and (b) rely on (after seeking out) third-parties for spare parts in case there's a break down, then I don't see how that makes using their machines any different from this DIY project. Besides the fact that, if successful, this project should result in *anybody* being able to cobble together a highly maintainable rotary processor for a *known price*, at *any time* (instead of getting the chance to be that lucky person that can score a used unit on Ebay, once every 4 - 5 months).

Again, the more I hear about this prospect, the more I'm convinced it's worth it to "reinvent the wheel"

 

[holmburgers]

Bottom line: I'd rather just be spending my time processing film than fiddling around building a processor to do so. And my time is worth enough that it's cheaper in the long run to just buy the phototherm than it is to spend the time to build a processor.

I'm sure a lot of people will agree that building/designing something can be just as fulfilling as doing photography. It's really a totally different hobby altogether, and to have two hobbies that are synergistic... well that's a beautiful thing!

Large parts suppliers, like http://www.mcmaster.com/# for example have such an incredible selection that you could probably build a space shuttle if you had the time, let alone a film processor.

Certain basic parts will always be available and cheap. Modularity is the future, not proprietary.

 

[Roxy]

Hi, my first post here, but I wanted to add my experience. I built a water heater using a automotive block heater and microcontroller with temperature sensors with a GFCI outlet for safety. Its a pretty simple way to heat the water bath. The heater puts about about 600watts max which is enough to keep the bath plenty warm. I keep a lid on the bath to keep humidity down and warm the water faster. The circulator pump is a cheap 120v unit used for circulating water in a plant fountain, found at stores like walmart for low cost.

 

[77seriesiii]

just checking in to see how the project fares.

Erick

 

[Barry S]

Tony-- How's the prototype coming? Is this project still alive? Thanks.

Barry

 

[Steve Toner]

Hi guys. I thought I'd check in here and give you an update on this. Yes, the project is still alive. I'm working on the electronics and basically have the temperature control prototyped, but have been slammed by winter and that's causing me some delays as I scramble to take care of my house. My plan is to get this soldered up on a proto board and send it to Tony for his evaluation. Then we can look at the motor control and making up a printed circuit board for it.

I heard from Tony recently, and he has been swamped at work, so that's why you're not hearing from him.

btw, I've been lurking here for probably 5 years - never had anything useful to say until now

 

[Barry S]

Steve-- thanks for the update and kudos to you for working on the project. I think this is absolutely worth pursuing and would really benefit those of us that process our own film. I've found it's easier to get through to Tony via his blog.

-Barry

 

[belichten]

I like

though I am a Jobo user(i have a atl 1000 and a atl2plus) I would love to see some other machines to do my processing for me.

one thing is that I need the 25xx series and sometimes the expertdrums.
if a processor is capable of handling both drumtypes plus drums of other manufacturers it would be a perfect combination.
one thing is that I think that the rotation of the drums is geared is a good thing as they can be filled horizontically and thus have better evenness in developing.
a good idea is the modularity. some people also do large prints and need the paperdrums which can get pretty big.

if there is a unit which costs around 300€ and takes the jobo 25xx and expertdrums I will instantly buy it.

 

[Steve Toner]

Here's a sneak peek at the current prototype of the electronics for anyone interested:

YouTube Video

 

[jon.oman]

Cool! Is the motor strong enough? Some tanks with solutions can be rather heavy!

 

[Steve Toner]

Right. I'm not in charge of motor specs, but this one claims 28 in-lbs of torque, for what that's worth... I haven't tried running it with a load on the motor, as the power supply I'm currently using to run the motor is a bit under-spec'd...

 

[Barry S]

Steve-- Thanks for posting--things are looking good. I concur with Jon about the need for a strong motor to turn Expert drums with a lot of solution and the need for drums to be fillable while horizontal and rotating.

 

[Steve Toner]

The motor driver chip that I've used can handle a bigger motor - this one draws about .25A at no load, and spec says about 1A at full load. The driver chip can handle a motor that draws over 2A at full load. More than that and it'll need a different driver. But the control circuitry and software will stay the same...

 

[Barry S]

Thanks. Not sure what gearing is planned, but it would be nice to make sure the expert drums do two full rotations before reversing, and I'd like the ability to turn off reversing.

 

[Steve Toner]

The gearing is built into the motor - it's intended to be direct-drive from there. We'll be releasing the software as open source, so you'll be able to make mods if you want. Want 3 rotations instead of 2? It's just a parameter in a header file...

Turning off reversing is possible without modifying the software. You can wire a switch that cuts off the optical sensor signal to the CPU and it won't be able to count revs, so won't reverse...

 

[Barry S]

Beautiful. I'm looking forward to purchasing the kit.

 

[kwall]

I can see serious value in buying the kit. The older processors just won't last forever. One built from commodity parts with open source software, though, will last forever. Not because the parts will, but with open source and commodity parts, modularity allows for easier replacements and substitutions.

 

[Edtog]

Good luck with the project, would be nice to know that there will be a replacement for my CPP2 when, or if, it breaks.

 

[Diapositivo]

Steve, you seem to be heading straight to the Finish line. The only questions I have are:
Is the motor fairly common?
If the motor breaks, and the model is out of production, is it replaceable with a different kind of motor?
Is it possible to vary the rotation speed?

Congratulations for the results so far. Now you know there's no coming back!

 

[AlbertZeroK]

I like it, but would love to see more timing functions, especially for us that do e-6 processing. I also think the LCD is too small. Are you going to supply a PC board? If so, can we get some extra headers or a prototyping area? I'd love to add a foot switch and a loud buzzer!

Great work!

 

[Steve Toner]

Steve, you seem to be heading straight to the Finish line. The only questions I have are:
Is the motor fairly common?
If the motor breaks, and the model is out of production, is it replaceable with a different kind of motor?
Is it possible to vary the rotation speed?

Congratulations for the results so far. Now you know there's no coming back!

I don't know how available the motor is in Italy, but it's a stock item here in the states. The electronics don't care too much what motor is being used - as long as it operates at 24VDC, has enough torque, rotates at the proper speed, and doesn't draw too much current, it's something that can be substituted.

As far as rotation speed goes, the current software only runs at a single speed (full motor speed). However, the processor has a PWM circuit built in, so I will add a low speed option. According to a Jobo document that I don't have handy right now, the speed is really not that critical, but Ilfochrome does work better at about 25 RPM, so that'll be the low speed...

Edit: Here's the Jobo document: http://www.jobo.com/jobo_service_analog/jq/jq9904.htm

 

[Steve Toner]

I like it, but would love to see more timing functions, especially for us that do e-6 processing. I also think the LCD is too small. Are you going to supply a PC board? If so, can we get some extra headers or a prototyping area? I'd love to add a foot switch and a loud buzzer!

Great work!

Bearing in mind that we're using the Jobo processors as the basis for this design, and the Jobos do not have any timing functionality, I'm looking at a followon project that would be a process timer, but as a separate device. There are not really any spare inputs/outputs on the processor we're using for this device either. That's to keep the cost down (although the CPU is not really a major part of the overall cost). I don't want feature creep to delay this version or drive the cost up...

We'll be making up a PC board. The current draft does have an optional header that would supply the SPI bus signals (the LCD display is an SPI device). You could use this to drive a different display if you wanted to. I don't think there's going to be enough room on the board to provide a prototyping area. Again, a cost consideration. We can get MiniBoards (3.8" x 2.5") at a very good price, so that is the size the PC board will be. The schematic will also be published (under GPL or FDL - not sure yet how that'll work), so you're free to use it as the basis for your own PC board design that adds extra functionality.

 

[kwall]

The schematic will also be published (under GPL or FDL - not sure yet how that'll work), so you're free to use it as the basis for your own PC board design that adds extra functionality.

I'd suppose that a schematic would fall under the FDL, but GNU have made what should have been a simple decision pretty damn complicated with front cover texts, back cover texts, and invariant sections. Sheesh. I opt for Creative Commons licenses when I can, but, of course, it's your design. Perhaps I should just butt out and mind my own business, eh?

 

[Steve Toner]

I'll add Creative Commons to my list of licenses to my list of possibilities that I need to evaluate.