i've also played with old "analog" legos motors, gears, camera and time lapse and had problem of rotating/moving too fast. Lately I had an idea to use analog clock to overcome this limitation: maybe it's possible to use "seconds arm" with aluminum foil on it and two wires (on connected to that aluminum and other, static waiting for the arm) as a switch that would turn on the lego motor for 1sec every minute. I don't know if it's practical and if it would work - haven't tried that - just an idea. Or if you have two motors you could use other motors and some gears instead of clock.