On rare occasions, for scan maps with homogeneous coverages in array reference frame, the exposure map overlay can display one scan less than for certain values of the orientation angle. The AOT overlay display functionality is the reference in case of difference.
- Implication for user: the predicted exposure map can be smaller than the one defined in the AOR.
- Recommended action: rely on AOR overlay to assess mapped area instead of exposure map.
Latest instrument ground tests have shown that the time spent per grating position in this mode is too low.
- Implication for the user : observations may produce unusable data.
- Recommended action: A minimum repetition factor of 2 must be entered in HSpot for AORs in chopping/nodding (bright lines).
Although the wavelength switching mode is currently available in "pointed" and "pointed with dither" in HSpot, this option will be disabled in the future.
- Implication for the user : AORs that use this option will become invalid and will have to be re-entered before execution.
- Recommended action: Wavelength switching should only be used in combination with the mapping pointing mode, with a minimum raster size of 2 x 2.
In the observing mode "mapping with OFF position", if the OFF position is defined relative to the centre of the map, i.e. option "by offset", negative relative offsets are not possible, due to a software bug.
- Implication for the user : relative OFF positions towards the south or the west are not possible.
- Recommended action: define an absolute OFF position with the option "by position".
A range scan defined in the [55-73] and [102-210] micron range will fail if
1) The short wavelength edge is between 110 and 120 microns
2) The long wavelength range is above 120 microns.
- Implication for user: A range scan in the [55-73] and [102-210] microns range that has the conditions defined above is not currently feasible. The parallel range in the extended 2nd order cannot be performed.
- Recommended action: change the wavelength settings to "Range scan in [71-98] and [102-210] microns (2nd and 1st orders)", if it fails for the [55-73] and [102-210] micron range. It will be possible to change back to the [55-73] and [102-210] microns range scan in the next HSpot release.
Range scans defined in the second order with the red edge wavelength lower than 73 microns are not possible due to a software bug.
- Implication for user: this range shall be performed in the third order instead.
- Recommended action: If a range scan fully bracketed in the range 71-73 microns is to be entered in HSpot, the user shall select the third order, where the line sensitivity is better (but not the continuum sensitivity), and switch back to second order in a future HSpot version is needed.
Range scans defined in the first order with the red edge wavelength lower than 105 microns are not possible due to a software bug.
- Implication for user: Range scan fully bracketed in the range 102-105 microns are not possible.
- Recommended action: Extend the red edge wavelength beyond 105.0 microns to make is possible in HSpot.