ducku
Hello,
My SW-DuKa is notoriously cold, and it takes a very long time to heat up with the wood-burning stove because of the size of the room. I’m therefore thinking of getting some tray warmers, for example from Kaiser. Now I’m not sure whether it makes sense to treat the stop bath and the fixer to a tray warmer each as well. After all, the Kaiser tray warmers are quite expensive. I definitely want to get one for the developer bath, but what do you think about the stop and fixer baths?
Best regards,
Florian
WolfgangF
Hello Florian,
The temperature of the stop and fixer bath isn’t all that important, but it shouldn’t really be below 17 degrees, otherwise you’d have to extend the times significantly.
For larger trays (approx. 30x40 cm), a small aquarium thermometer is a good alternative to a tray warmer. These come with a thermostat set from 20 degrees and cost around €20.
Alternatively, you could heat up a large tray as a water bath using the aquarium thermometer and place the other trays inside it.
Good luck, Wolfgang
Tandemfahren
Erm... you mean an aquarium heater, not a thermometer, right?
By the way, you can get perfectly decent heating mats for a fiver. The temperature really isn’t that critical. Around +/- 3° is enough, and depending on the developer, even a bit more.
The ‘factor method’ is the magic word. If you multiply the exposure time by 6, you’re already on the right track.
Frankgröße
ducku
Hello,
Thanks for the tips. What do you think of the following combination: (more expensive) shell worms for the developer, and a heating mat each for the stop bath and fixer? That would cost me a total of €200 new, assuming I’m looking at 30x40 cm trays. What size heating mat should I choose, or what wattage?
The idea of using an aquarium heater is great at first glance, but I’m afraid the heat distribution might be a bit of an issue. They get quite hot in places, which means you’d have to be stirring them constantly.
Best regards,
Florian
Tandemfahren
You can do that, of course, but it’s a bit over the top. For terrariums, there are mats rated at around 8–20 W. A 20 W one should be more than enough.
You could also warm up the Stop and Fix before the session, for example in a water bath or using a radiant heater.
Frank
Wolf_XL
...you have to prepare a fresh stop bath with warm water every time anyway, and I’d simply store the fixer in a warm room...
ducku
I think I’ll get two 20W heating mats and put them under the developer and fixer tanks. It won’t cost the earth.
€
Alternatively, I’ll have to put a bigger oven in the darkroom. :-) The little wood-burning workshop oven is obviously not powerful enough.
€
Best wishes,
Florian
pikespeak
It’s much the same for me, as my darkroom is in my second home and I don’t usually heat the room.
When I’m planning a day in the darkroom, I go there the day before and heat the room to 22°C. That’s obviously difficult with a wood-burning stove.
I have an oil-filled radiator. For last-minute sessions, I have heating mats for seed trays tucked under my flooring. That works quite well.
For film development, I’ve moved the chemicals over there, and I just reel the film in the cold darkroom. The developing is done here in my office at room temperature. You could also heat up the CP2, but that takes too long for a single roll of film.
ducku
Hello,
I’ve now bought two 20W heating mats on eBay. I’ve placed them under the developer and the fixer. It works a treat. I can highly recommend them. The temperature remained remarkably constant for over three hours.
Best regards,
Florian
