The modified webcam was highly sensitive in the infrared, although it's hard to be specific because of its auto-exposure feature. In the photo at right, the webcam was attached to an 80-mm Nikon lens with masking tape. Because of the small sensor, this produced a huge telephoto effect, and it was necessary to point it at a pine tree a few hundred meters away. Re-attaching the original lens would probably have worked better, but it would probably be necessary to re-focus it. This is easy because the plastic lens screws in and out. Note that if any dirt falls on the sensor, it's there for good, as there is no way to clean the bare chip.