Sous Vide Equipment for Developer Temperature Control

[imokruok]

So, for those who don't know, sous vide cooking is cooking 'under vacuum.' You place food in a vacuum sealed pouch and cook it in a water bath - sometimes for 24-48 hours at a time - at a very controlled temperature. (e.g. Exactly 140 deg. F for two days.) This is accomplished with a controller attached to a rice cooker or buffet table - the controller unit has a temperature probe that goes in the rice cooker full of water, and then the controller turns the cooker on and off as necessary to keep the temp exact.

Here I am looking at my sous vide equipment and it dawns on me - I can probably use it to hold developer chemicals at temperature as well as food. I haven't done this yet, but am suggesting an idea and also wondering if anyone else has done something similar.

If anyone wants to take a look at the equipment, here's the company where I got my unit with a couple of pics of what the set up looks like: http://is.gd/8yibE

It seems to me that if we're going to be anal about temperature control of developing chemicals, this could be a pretty decent way to do it, short of buying a JOBO. At least this way you could keep your bottles regulated until you're ready to use them.

 

[MattA]

There is another sous vide controller on the market with better sous vide safety features and accuracy.
SousVideMagic
The company is known for sous vide cooking support. Check it out!

 

[MattA]

BTW
I also use SousVideMagic it to control my water bath temperature for developing film negatives!

 

[zerobuttons]

If you don´t have to keep chemicals temperature controlled for days in a row, it doesn´t have to get that complicated.

When developing, I fill a plastic tub with water tempered at 20 degrees Celsius and place three measuring containers in it containing the right amounts of mixed developer, stop bath and fixer.
While the chemicals are achieving the right temperature, I load the tank reels with film.
When the chemicals have achieved the right temperature, I start processing. While processing I can just lift the measuring container out of the tub and be sure that the contents have the right temperature.
It does take some amount of water in the plastic tub to be sure that the temperature is steady all the time while processing, but on the other hand I don´t have to worry about it from the moment I start processing.

 

[Penceler]

Nice.... but I'll stick with my crock pot (slow cooker). I only need perfection for a few minutes.

John
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[aizan]

how much do immersion circulators cost? i've thought about doing sous vide a little, but never got any appliances.

 

[imokruok]

how much do immersion circulators cost? i've thought about doing sous vide a little, but never got any appliances.

Pretty pricey ($1,000-ish), although if you are willing to take a risk on an ex-lab one, you might get off easy for a few hundred bucks.

Also, zerobuttons, totally with you on the bath at 20 deg C. I wouldn't do serious temp control for black and white. The water from my sink is pretty stable once I get the handle just right. But if I'm doing color, I'm worrying about maintaining temp in the chemicals and in the tank.

 

[Penceler]

It really comes down to how long do you need critical temperature control. The answer, I suspect, will vary based on how many rolls you're processing but for the hobbyist, it's a very short time indeed.

Even in E6, modern chemistry gives you a 1 degree swing (+/- 1/2) but its only critical for the developing stage - abut 6 minutes. After that it jumps to +/- 2 degrees, then +/- 5 etc.

Try an experiment. Take an uninsulated plastic cup. Fill it with 10 oz of water at 100 degrees and just let it sit out on your counter for 6 minutes. If your results are like mine, you'll find that the temperature drops about 6 degrees in a room temperature environment. Preheat the cup and the temperature drop is down to 4-5 degrees. Use an insulate pad (aka pot holder) under the cup and its 4 degrees. You've got 1 degree to play with.

Yep, we're only talking 3 degrees for 6 minutes.

Lets not over complicate this.

John

 

[imokruok]

Lets not over complicate this.

John

Understood! Actually, my whole idea was to make the process simpler. Rather than stand over a stopped-up sink, using the hot water tap to regulate, it would be a whole lot easier to throw the bottled chemicals in a tank, set the temp, and walk away for an hour letting them all heat up.