An extendable galaxy number count model

I review galaxy number count models and present ncmod, an extendable and general purpose model for comparing and interpreting the results of field galaxy survey data. I develop techniques and software for converting the results of a survey done in one filter into another filter for direct comparison with other surveys. Comparison of the data from surveys that differ greatly in wavelength coverage or sensitivity is of necessity model dependent, but comparison between similar surveys can be done in a relatively model-independent way. I extrapolate existing number counts into the ultraviolet and thermal infrared. The model is used to predict the results of future space missions, including STIS and NICMOS on Hubble space Telescope, Infrared Space Observatory, Space Infrared Telescope Facility, and Next Generation Space Telescope.