Temperature ranges for emulsion

[fdonadio]

Hello!


I'm still in the planning stages of emulsion-making and coating.

Since it's Summer down here in Brazil, I'm very worried about how temperature can influence coating and drying. We're getting up to 41 deg Celsius (100-something deg Fahrenheit) lately and it's very hard to keep a water bath at 45 degrees C (for example) with that ambient temperature.

So, what would be the recommendation for darkroom ambient temperature, specially for drying emulsions on paper? I can get air-conditioning, if it's needed...


Regards,
Flavio

 

[dwross]

41C is a great temperature for drying emulsion, but if your air is humid, you'll want to use a de-humidifier. I live next to the ocean, and my humidity is between 90 and 100 percent most of the year, but it's almost always cool enough to need a space heater in my darkroom. That does a good job of drying the air. I can't imagine working in that warm a darkroom, though. A/C sounds like a great idea! Shouldn't be too expensive for a small space.

Question: I'm missing something. If your darkroom is that warm, I would think it would be fairly easy to keep a water bath just a little warmer (??)

 

[fdonadio]

41C is a great temperature for drying emulsion, but if your air is humid, you'll want to use a de-humidifier.

OK, so I'll need a cabinet with a heater in the winter... We get down to zero here, sometimes!

Question: I'm missing something. If your darkroom is that warm, I would think it would be fairly easy to keep a water bath just a little warmer (??)

Because temperatures get high too fast, requiring you to take the beaker out of the bath all the time. Even digitally-controlled water bath equipment can't guarantee precision in temperatures 5 to 10 degrees above room temp. Now, try to imagine doing that by hand, looking at a glass thermometer!


Regards,
Flavio

 

[Photo Engineer]

The range of 20 - 40 C is good and the range of about 30 - 70 RH is good, but at the higher RH, emulsions dry slowly and can be tacky.

PE