How do you get your development chemicals warm?

Discussion in 'Minox' started by steve_d|6, Feb 15, 2010.

  1. Hi,
    As you who develop your b&w film know, the specs call for the chemicals to be within certain temp parameters. Typically the required temps range from 68* to 75* F (sorry, I still speak F).
    Its now winter and the house, the dark room and especially the chemicals are well cooler than that.
    I'm looking for suggestions on how you warm them in order to get a solution as required by the development sheets?
    Best
    Steve
     
  2. There are a few ways to warm up chemicals. All of them (that I know of) involve putting the containers of the chemicals in a water bath. The cheapest (but most wasteful) way is to take a tray, and run warm water in it until it is the correct temperature and let the chemicals sit. Unfortunately, this isn't that controllable. The next way is to get an aquarium heater in place it in said tray of water. That will regulate and keep the temperature correct. The final way is to spend $$$ and get a water bath/recirculator. That method isn't worth it for B&W. With any of those methods, you'll have to let the chemicals sit for about 30 mins in the water bath to get up to temperature.
     
  3. Assuming this is being done in the usual filmdevelopment tanks, the usual way is to use graduated glass or plastic containers (I use the ones I buy in photo stores when they still existed) and I pour the chemicals in each one that I'm going to pour into the tank. I then take the sink and either put in hot or cold water with ice in the sink depending on whether I need to heat up the chemicals or cool them down. I then put a thermometer in each one till the reach within a degree or two from the desired temperature and then I take them out. If I overshoot, I reverse the process. Note that since I store my chemicals premixed in the same place, they all start out the same temperature, and since I'm using the same number of ounces of each, they all warm up or cool down at pretty close to the same rate since they're effectively mostly water.
    With traditional black and white chemicals, really on the developer matters that much, so often it's enough to get the developer to the right temperature. If your house is that cold, then you can warm them up using the hot water in the sink method till they're in a general range or just warm them all up together in the sink at the same time and just watch the developer.
     
  4. It's no big deal really... The wet side of my darkroom has two exterior walls with no direct climate control, so my chemestry gets a bit cool too.
    If the chemicals are just a little cool (63° to 65° -ish), I'll fill the sink with water that is about 75° and float the bottles for a few minutes. If they are REALLY cold, you can float them in HOT water but be careful, you might be surprised how quickly you can warm them up past 75°.
    Unless your darkroom is crazy cold, you won't loose that much heat out of the chemistry in the 7-12 minutes it's in the developer (stopping and fixing are less critical - feel free to fix a few minutes longer).
    Liquid to liquid heat transfer is pretty quick, but liquid to air isn't so much, especially if you are using the standard plastic Minox tank. A stainless tank might loose a little more, so you might take a degree or two of fudge room.
     

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