10.1 Introduction

This chapter provides reference material to help you select your filter and detector configuration and determine your observing plan (e.g., total required exposure time, and number of exposures). For the most part, this chapter is organized by filter and detector. For each imaging mode, the following are provided:

Plots of total system throughput as a function of wavelength.
Plots of the time needed to achieve a desired signal-to-noise ratio vs. magnitude for all filters for a point source and a one square arcsecond extended source.
Tables of color corrections AB_V to go from Johnson V magnitude to AB magnitude, and for SBC, to go from GALEX NUV and FUV to AB magnitude.

The Tables and Figures that are provided in this Chapter may differ slightly from the current results obtained using synthetic photometry software. Such differences are due to the fact that the component throughput tables are updated as needed to reflect the latest calibration results. Please contact the HST Help Desk if you have any questions regarding this subject.

«Previous Next»

ACS Instrument Handbook
- • Acknowledgments
- • Change Log
- • Chapter 1: Introduction
- Chapter 2: Considerations and Changes After SM4
  - • 2.1 SM4 Repair of ACS
  - • 2.2 ACS/WFC Observations in Cycle 33 and Beyond
  - • 2.3 Comparison of WFC and UVIS
  - • 2.4 Comparison of HRC and UVIS
  - • 2.5 Dithering Considerations
  - • 2.6 CTE Considerations
  - • 2.7 SBC Considerations
- Chapter 3: ACS Capabilities, Design and Operations
  - • 3.1 ACS Location in the HST Focal Plane
  - • 3.2 Instrument Capabilities
  - • 3.3 Instrument Design
  - • 3.4 Basic Instrument Operations
  - • 3.5 ACS Quick Reference Guide
- Chapter 4: Detector Performance
  - • 4.1 Overview
  - • 4.2 The CCDs
  - • 4.3 CCD Operations and Limitations
  - • 4.4 The SBC MAMA
  - • 4.5 SBC Operations and Limitations
  - • 4.6 SBC Bright-Object Limits
- Chapter 5: Imaging
- Chapter 6: Polarimetry, Coronagraphy, Prism and Grism Spectroscopy
  - • 6.1 Polarimetry
  - • 6.2 Coronagraphy
  - • 6.3 Grism and Prism Spectroscopy
- Chapter 7: Observing Techniques
  - • 7.1 Designing an ACS Observing Proposal
  - • 7.2 SBC Bright Object Protection
  - • 7.3 Operating Modes
  - • 7.4 Patterns and Dithering
  - • 7.5 A Road Map for Optimizing Observations
  - • 7.6 CCD Gain Selection
  - • 7.7 ACS Apertures
  - • 7.8 Specifying Orientation on the Sky
  - • 7.9 Parallel Observations
  - • 7.10 Pointing Stability for Moving Targets
- Chapter 8: Overheads and Orbit-Time Determination
  - • 8.1 Overview
  - • 8.2 ACS Exposure Overheads
  - • 8.3 Orbit Use Determination Examples
- Chapter 9: Exposure-Time Calculations
  - • 9.1 Overview
  - • 9.2 Determining Count Rates from Sensitivities
  - • 9.3 Computing Exposure Times
  - • 9.4 Detector and Sky Backgrounds
  - • 9.5 Extinction Correction
  - • 9.6 Exposure-Time Examples
  - • 9.7 Tabular Sky Backgrounds
- Chapter 10: Imaging Reference Material
  - • 10.1 Introduction
  - • 10.2 Using the Information in this Chapter
  - 10.3 Throughputs and Correction Tables
    - • WFC F435W
    - • WFC F475W
    - • WFC F502N
    - • WFC F550M
    - • WFC F555W
    - • WFC F606W
    - • WFC F625W
    - • WFC F658N
    - • WFC F660N
    - • WFC F775W
    - • WFC F814W
    - • WFC F850LP
    - • WFC G800L
    - • WFC CLEAR
    - • HRC F220W
    - • HRC F250W
    - • HRC F330W
    - • HRC F344N
    - • HRC F435W
    - • HRC F475W
    - • HRC F502N
    - • HRC F550M
    - • HRC F555W
    - • HRC F606W
    - • HRC F625W
    - • HRC F658N
    - • HRC F660N
    - • HRC F775W
    - • HRC F814W
    - • HRC F850LP
    - • HRC F892N
    - • HRC G800L
    - • HRC PR200L
    - • HRC CLEAR
    - • SBC F115LP
    - • SBC F122M
    - • SBC F125LP
    - • SBC F140LP
    - • SBC F150LP
    - • SBC F165LP
    - • SBC PR110L
    - • SBC PR130L
  - • 10.4 Geometric Distortion in ACS
- • Glossary

10.1 Introduction

On this Page