Introduction

This chapter contains instructions for creating a focus model for the ROTSE-III telescope system. At least one night must be dedicated to taking focus data, and some follow-up focus data must be taken at different temperature ranges. Focus data is built up with many ``focus runs'', described in Section 4.3.3 and Table 4.1. Each focus run is a set of exposures taken on a field at regular focus position intervals.

Please see Chapter 2 for information on starting the system. Chapter 4 should also be consulted on how to make modifications to the the astrod.conf scheduling configuration file.