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6. What do I do if I need precise centering for a target that’s too bright for WATA?
- (1) use the standard MSATA algorithm which utilizes faint reference stars in the field, (2) acquire a nearby fainter star and offset to the desired bright target (fixed targets only), or (3) observe without using any target acquisition.
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1. The ETC will give me a warning if I start inputting parameters that are not supported
by APT, right?
- yes?
2. Can I upload a custom spectrum for my source for ETC calculations? What information
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tedious... Is there a way to speed this up?
- Unlike other exposure time calculators, the JWST Exposure Time Calculator (ETC) does not provide an option for reverse calculation of exposure duration parameters starting from a given signal-to-noise ratio (S/N) because there is often no unique solution for a given subarray/readout combination in terms of groups, integrations, and exposures. Instead, a batch expansion capability is available to test a number of different detector parameters (groups or integrations) to determine which set of parameters results in the desired S/N.
5. When should I use the IFU Nod off Scene strategy?
- For IFU Nod Off Scene, there is no source flux in the off-source nod position because it is completely off the scene and only contains the sky background. Only half of the exposure time required for the IFU Nod Off Scene strategy is on-source and hence the SNR is lower.
6. I would like to do additional analysis beyond what the ETC reports. Is there a way to
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