Space Telescope Science Institute   10.3 Orbit Use Determination  11.1 Introduction

Chapter 11:
Techniques for Dithering, Background Measurement and
Mapping


In this chapter . . .
Introduction
Strategies For Background Subtraction
Chopping and Dithering Patterns
Examples
Types of Motions

In this chapter we deal with techniques for using small scale motions to remove localized detector non-uniformities and to improve spatial sampling; chopping to remove the thermal background of the telescope, and for mapping areas larger than the size of the field of view of the NICMOS cameras.

NICMOS patterns have been created to enable observers to perform dithering, chopping, and mapping, and these patterns are significantly different than those described in earlier versions of this handbook.


 10.3 Orbit Use Determination  11.1 Introduction
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