Direct Heating Film Chemistry: Why Panterla Is Moving Beyond the Water Bath
A note on the name. “Panterla One” is the working name for this automatic film developing machine — nothing is finalized yet, but it’s the name used for the project going forward in these engineering logs. Summary. I tested direct heating as a replacement for the traditional water bath in the Panterla automatic film development machine. The prototype used a 24 V / 150 W immersion heater, approximately 500 ml of water, active circulation, a digital temperature probe, and closed-loop temperature control. The measured linear heating rate was 3.59°C/min, corresponding to an extrapolated 20→38°C heat-up time of 5.02 minutes. During a separate steady-state test, the recorded temperature had a standard deviation of only 0.033°C over the analyzed four-minute window. The experiment also exposed a separate problem: the control probe and external logger disagreed by about 0.3°C, showing why stability and absolute accuracy must be treated as two different engineering problems. ...