> but I'm not sure you can really make a knob that works accurately for both 30 seconds and 30 minutes.
Not terribly difficult. An encoder and software to handle "acceleration". Move the knob slowly, and it steps by a small amount (say, 30s). Move the knob quickly, and it jumps by more per degree of change. My main camera lens's focus works like this, and it's great. This does require care in implementation, getting the acceleration curve right is hard.
Not terribly difficult. An encoder and software to handle "acceleration". Move the knob slowly, and it steps by a small amount (say, 30s). Move the knob quickly, and it jumps by more per degree of change. My main camera lens's focus works like this, and it's great. This does require care in implementation, getting the acceleration curve right is hard.