Welcome to version 3.0 of the JWST ETC!
This release features accuracy updates based on inflight measurements, updates to IFU strategies, and new instrument-specific options for Cycle 3: see the Release Notes for details, and be sure to review the Known Issues for this release.
When you log in, workbooks from ETC 2.0 and earlier will be marked with a previous version number in the "Ver" column:
Be sure to review the Known Issues with this release.
Calculation run times for certain instrument modes are longer because the underlying computations are more complex.
The use of highly sampled spectra may result in significantly longer run times for spectroscopic modes, with the longest run times for higher resolving powers.
Occasionally, the UI may appear to be unresponsive or stalled. Try reloading the page; this often clears the issue.
System performance depends on usage/load; if the system appears unresponsive, wait 1-2 minutes. Please avoid repeatedly clicking, because this will make the problem worse. If the system remains unresponsive, contact the JWST Help Desk.Accuracy of ETC Calculations
This version of the ETC is intended to help users plan observations for General Observer (GO) programs. The ETC approximates our current best knowledge and understanding of the performance of the JWST instruments, based on inflight measurements and calibrations. It has been validated against inflight observations analyzed by the instrument teams. Users should exercise appropriate caution when interpreting results from the ETC. A number of known issues remain, which may affect predicted sensitivities. See Known Issues for additional details.
The ETC is not intended to be a complete observation simulator, and some higher-order effects are not accounted for, such as field distortion.