If you're mixing a solution from scratch and the formula does not specify a temperature, what temperature do you use?
Not all of the published formulas include a mixing temperature so I suppose it comes down to the solubility of each ingredient.
Thanks
40 to 50 degrees C should be fine, I do not obsess about it. Perhaps one exception would be ascorbate based developers. IIRC a lower temperature is what Kodak proposes for mixing Xtol.
I would consider 125ºF/50ºC to be as high a temperature as I would use. I understand that high temperatures can accelerate oxidization, which is not desirable. I generally use 100ºF and when everything is dissolved, make up the quantity with room temperature water. Works for me.
It's a bit more complicated than using the oft quoted 50C. This temperature should be fine for developers and some other solutions. However there are exceptions. For example fixers should be mixed in cold water to prevent sulfurization. Then too if sodium/potassium hydroxide is called for then also use cold water. Easily oxidized developing agent like pyrogallol or Amidol need cool water.