NICMOS ETC no longer exists and we don't expect to have one in near future.
Known Issues with previous versions of ETC
- As of 4 December 2007, in conjunction with the Cycle 17 Call for Proposals, the NICMOS ETCs have been updated and revised to reflect a number of corrections and improvements relative to those used in previous years. We recommend that observers use these most up-to-date ETCs for their NICMOS calculations.
- On November 8, 2004, an updated NICMOS ETC was delivered. This delivery included a second new user interface for NICMOS grism spectroscopy. Other updates to the ETC include calculation of sky background given target RA and DEC coordinates and the ability to upload user spectrum files directly to the ETC server from inside the browser interface (instead of FTP-ing the file to the public STScI anonymous FTP server). Previous enhancements to the ETC delivered November 25, 2003 are listed here.
- In the period between July 2004 and 28 April 2005, the ETC contained an error that led the ETC to overestimate the detector quantum efficiency. We recommend that any calculations performed in the affected period be repeated in order to obtain the correct exposure time or signal-to-noise estimates.
- Old CGI ETC Limitations and Known Problems
For coronagraphic observers, please refer to this advisory note.
For problems or questions, please email help@stsci.edu.