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Hubble Space Telescope
Exposure Time Calculators

Exposure Time Calculators

The Exposure Time Calculators (ETCs) are online tools that predict the count rates and S/N in various observing modes given specified source characteristics.

IR Channel ETCs

UVIS Channel ETCs

TINY TIM PSF Simulator

Spectroscopic Image Simulator

*** Last Updated 15 February 2011 ***

Known Issues

(for all ETCs other than the ST-ECF Spectroscopic Image Simulator)