Abstract NuTel is an experiment to observe the ultra-high energy cosmic tau neutrinos with the earth skimming technique. Mountains are used as targets to convert tau neutrinos to tau leptons and also as a filter to block cosmic ray backgrounds. The signature of a high energy tau is an air shower that originates from the mountains or the ground. NuTel is designed to observed the Cherenkov in such air showers. The optical and electronic systems of NuTel have been designed and are being built and tested. A simulation program to describe both the optics and the electronics is developed. Based on the simulated photo-image, the energy and inicident angle of the shower can be determined by a reconstruction program, which also handles background filtering and desaturation. It is found that the simple and rough filter produces the largest error due to loss of accuracy in position and amplitudes.