Scanning the light every 5 minutes is going to reveal a very small percentage of the animals you call in most cases. Your best bet is a constant burning light source, especially on a Rheostat or dimmer control to prevent "Burning" an animal before you're ready for the shot. Lightforce makes the best scope light, hands down, but they are expensive. Rechargable spotlights are too bright, require an extra hand to shine with, don't have dimmers and are prone to going dead rather quickly. Pros and cons-