
	User's Guide Contents
	Return to ETC Welcome SYNPHOT SNR and Exposure Time SNR Time Optimal SNR Spectroscopy Target Acquisition Basic Use Page Heirarchy Reference Extraction Regions Spectral Distribution User Spectra Other Spectra Extinction Normalization Background CCD Parameters ID Number Calculations SYNPHOT Calls Call Descriptions Call Parameters NICMOS Spectroscopic Extraction Regions Tables Spectral Elements NICMOS Filters NICMOS Dispersers ACS Filters and Dispersers COS Dispersers WFC3 Filters and Dispersers STIS Filters and Dispersers NICMOS Tables COS Tables STIS Tables and Topical Help

ETC Web Page Hierarchy

The HST ETC consists of a server that handles the calculations and a collection of input pages for each of the 4 instruments (ACS, NICMOS, STIS and COS) and their respective science modes (imaging, spectroscopy, coronagraphy, ramp filters and target acquistion).