Quote Originally Posted by ann
if it is weeks and even months between sessions i would look at the way you are storing the developer. oxidation will occur if not carefully capped.
You can check the quality of the developer in real time if you use this rule of thumb: Dektol @1:2 begins to produce mid-tones in 30 to 35 seconds. Develop exactly 4x the time it takes to see mid-tones. This will compensate for oxidation, temperature variation, sun spots and hangovers.

Tip 2: Stop down one stop on the enlarger lens and double the exposure time. This will increase accuracy and eliminate some effects of current fluctuation, bulb warm-up time and dodge-burn spasticity.