Now I'm looking at that lens. It uses a 4.5v 650 mAh battery to power the shutter. I have some small AA battery holders that will mount on the back of the board out of sight I could wire into it as a replacement and also mount a toggle switch to kill the power and save the battery life. I need to know what value of load resistor I should put inline to keep the current from the AA's down so the shutter coils don't get burnt. The AA's run about 2000-3000mAh each. I don't know what formula needs to be applied to find the right values. Do I need to measure the current the shutter draws during operation to work this out? Do we have a kindly electrical engineer out there who can help?