What do you guys do to keep your home developing water at a consistent temp?

[Treymac]

Hey guys. I want to start doing my own developing at home. I know the process and have everything figured out, but one thing still perplexes me. How do I keep the water at 20C? It takes a long time to play with the temperature knobs to get to the perfect temp, but I don't want to keep the water running during the whole developing process. Which means that every time I have to run water through the negatives I have to turn the water back on and readjust it

It would be simple to just collect enough water that equates to around 7 1/2 minutes of running water time and then just use that to wash the negs with, but that brings up other problems, like how to keep that water from changing temperature just by sitting there waiting to be used, or how to get the gathered water to continuously run over the negatives during the 5 minute cleaning process.

Just curious what you guys do. I plan to do my developing in the downstairs basement where it is very cold in the winter.

 

[RalphLambrecht]

Hey guys. I want to start doing my own developing at home. I know the process and have everything figured out, but one thing still perplexes me. How do I keep the water at 20C? It takes a long time to play with the temperature knobs to get to the perfect temp, but I don't want to keep the water running during the whole developing process. Which means that every time I have to run water through the negatives I have to turn the water back on and readjust it

It would be simple to just collect enough water that equates to around 7 1/2 minutes of running water time and then just use that to wash the negs with, but that brings up other problems, like how to keep that water from changing temperature just by sitting there waiting to be used, or how to get the gathered water to continuously run over the negatives during the 5 minute cleaning process.

Just curious what you guys do. I plan to do my developing in the downstairs basement where it is very cold in the winter.

If you have trouble with keeping running water at temperature, you might want to consider a sequence of several water exchanges and collect the water for that beforehand. Four to six exchanges should do the trick. Use your development tank to do the wash and a washing aid to minimize the amount of water you need.

 

[Mike1234]

Depending on where you live... in summer you need a chiller and mixer. In winter you need to mix from your water heater. It's a good idea to have a surge tank as well before and aft the mixing valve... at least aft.

 

[nickandre]

fill up a gallon jug with water at the temperature you need and then use that.

 

[Jadedoto]

I generally just have a big bowl that I put the tank in... My "cold" water generally comes out of the faucet a few degrees too warm, so I put in ice cubes until the desired temperature is reached, then I remove the ice cubes. I keep temperatures pretty stable like that, probably within a degree or two (I use a mercury lab thermometer that reads in 1degree increments).

To do the opposite (make warm water), I'm working on using an Arduino or perhaps a dedicated system to switch on and off a heater element to maintain higher temps...

 

[cmo]

In my lab I always have canisters with tab water, room temperature is 20° C. I use the water to dilute XTol 1:1 and to wash the films using the Ilford washing method. A few canisters are enough for dozens of films.

 

[glbeas]

Intellifaucet. Nuff said.

 

[RalphLambrecht]

Intellifaucet. Nuff said.

I was tempted to mention that, because it is a fantastic piece of kit. It complete takes care of water temperature control for you. You can forget about this problem and move on. Someone flushing the toilet in your house, turns on the washing machine, dish washer? Don't worry about it. Intellifaucet takes care of it within a few seconds. Unfortunately, it is the second most expensive piece of equipment in my darkroom. But, I would always buy it again.

http://www.hassmfg.com/search.pl/1263165459-76494?keyword=1092&submit=Search

 

[mikebarger]

Intellifaucet will not fix 75 degree water from the main.


Mike

 

[jeroldharter]

A water bath is helpful. The more volume the better for maintaining temp during development. The temp control during subsequent steps does not make much difference so long as you don't have wild temp swings.

For a water bath you could use a plastic storage tray, a darkroom tray, a pyrex baking dish, etc. Dev-Tec makes heated water baths with circulation but they are expensive. An alternative is an aquarium heater with an aquarium pump. They are slow but work OK.

I use a water bath for rolling BTZS tubes. I use a 12x17 darkroom tray filled almost to the top with water (I have an Intellifaucet which is cheating but you could do it manually also). Then you can use ice cubes + microwaved water to maintain the temp. I just picked up some re-usable gel packs from a medical supply house that can be put in the freezer for cold or microwaved for warm. They are in plastic and roughly 3.5 x 9 inches so they have alot of surface area for heat diffusion. Low tech but easy and reliable.

A great tool is the RH Designs Process timer that will adjust the development time based on a time:temp algorithm. Works well.

 

[JBrunner]

Water bath for chems. The developer is the one to be really spot on with. Wash temp is much less critical, 70f or so, just keep swings in check and not so hot as to cause reticulation.

 

[Leighgion]

I use a water bath for the development phase, but honestly haven't worried that much about the temp of my rinse water. Figure as long as the difference isn't too extreme, it doesn't matter enough for me to trouble over it.

 

[wclark5179]

I've always not worried too much about the water used to wash film. I try to keep it within 5 degrees or so of the fixer/s.bath/developer temp. For water I use to mix working solution I use the microwave oven to warm up the water a bit before mixing.
If there is too much of a variance between the chemicals as well as the rinse water reticulation can occur. I can check this all out with my trusty thermometer but I usually don't. Maybe I'm a little overconfident as doing this for 50 plus years or maybe careless but, at any rate, works for me.

 

[fschifano]

Really. That's all it takes. I have big kitty litter tray that I fill with water at close to the right temperature. Added in a fish tank heater and a very small submersible circulating pump that I had lying around from the days when I actually kept fish, to keep everything stable, and Bob's your uncle. For washing film, a gallon of water tempered in the bath along with the chems and the developing tank suffices. In winter, the cold tap dispenses water at about 48F, and that's too cold for efficient washing.

 

[JBrunner]

It's my understanding that slightly warmer wash water is actually a bit more effective, and cooler a bit less.

(Oh, In part 2 of the 120 developing video you can see the storage tray I use for tempering the developing process.)

 

[RalphLambrecht]

It's my understanding that slightly warmer wash water is actually a bit more effective, and cooler a bit less.

(Oh, In part 2 of the 120 developing video you can see the storage tray I use for tempering the developing process.)

That's right. Warm wash water is more efficient than cold water. I suggest to avoid water temps below 5C due to reduced washing efficiency but avoid temps above 27C due to softening of the emulsion.

 

[Jeff Kubach]

I hire cheap labor.

Jeff

 

[dancqu]

Day Light Tank Processing?

Stay out of the basement. Use a room temperature
jug of water. The Ilford wash sequence works well
and uses very little. Dan

 

[tkamiya]

I prepare a big jug of water and water bath, then I leave everything in bathroom for few hours so that temperatures equalize. As long as tap water is within 5C difference, I don't worry about it. If it is more than 5C difference, then I use the jug of water for 1/2 of washing, then use the tap water for the rest.

By the way, I made up a chart based on Kodak's published figures so that for every degree change between 65F and 75F, I have the correct development time for -15%, -10%, 0%, +10%, and +15%.

Challenge for me is the summer time where ambient temp rises to 83F or so in my house. Then, I have more of a problem keeping everything cool. Even in this condition, tap water is relatively cool so I don't need to worry that much about it.

 

[fschifano]

See this link from Ilford. It's pretty accurate for most MQ, PQ, and even ascorbate type developers like XTOL. It even works well for Rodinal. The usual caveats apply, and you'll probably need to fine tune for your methods and conditions.

 

[Vilk]

i made a tiny spreadsheet that calculates the required initial water temp, based on room temp (that's the temp of stored concentrate for me) and the relative volumes. i may adjust half a degree either way to account for the possible delta during those few minutes, nothing too obsessive

never noticed significant variation in those hundreds of negs so i guess it works (of course, the robustness of this approach will depend on both the material and the chemicals)

 

[Micky]

it's damn hot here in South Australia at the moment - last night I was in the darkroom at midnight, and it was 93 dg. far. outside, and the mains water temp was close to 83 deg. i just put my tray in a larger tray and add ice several times as required.

 

[Dave in Kansas]

Here in Kansas, my chemicals go from being too warm in the summer to being too cold in the winter, along with the tap water. So in the summer I put my jugs of chemicals, and a gallon of water for pre-wash and rinse in the refrigerator or freezer for a little bit to cool them, and in the winter I let the jugs soak in a sink of warm water to heat them up. For film developing, I can easily keep the developer right on, and the others stay close enough to the desired temperature that it doesn't matter. My darkroom in the basement generally stays cool enough in the summer for my print developer. That didn't used to be the case before air-conditioning. In the winter I sometimes use a heating pad under the developer tray to warm it up once in a while.

Dave

 

[largeformat pat]

I Use a jobo, during summer the tap and tank water are about 26c, I went to the discount store and purchased a few of those freezer blocks. Just float them in the water as you set up. When I'm done, a quick wash and dry and back into the freezer.

 

[nworth]

For black and white, I process at room temperature. Sometimes that gets a bit warm, but it is generally within reason. I simply adjust the water temperature (using the hot and cold taps) to about room temperature when mixing the solutions. After mixing, I wait a half hour or so. It works.