An automatic film processor sets new reference developer chemical temperatures and film transport speeds in accordance with user input at a keypad and disengages the film transport motor under microcomputer control to prevent further introduction of film until sensed actual developer temperature is within an acceptable tolerance of the new set temperature. A "wait" light is modulated to flash with increasing frequency as the gap between actual and set reference temperature is narrowed. Manual override is provided to re-engage the film motor even though the new set temperature has not been reached. A buzzer signals a feed in the override mode.