This section describes the time estimation details as reported by HSpot by pressing the "Details" button in the time estimation window (see for example Figure 6.10). The details are complementary to the "Time Estimation Summary". It is possible to select the verbosity level by ticking the relevant "Message level" buttons as shown in Figure 6.22.
Because the observing modes for SPIRE have different timelines and instrument commanding so the detailed messages are different. Here we illustrate the different verbosity levels using SPIRE Photometer small map mode. The observer can experiment with the other observing modes in HSpot.
Note that the "Observation Completed" time, shown at the end of the message window, equals the "On-source integration time" + the "Instrument and observation overheads" reported in the "Time Estimation Summary" window + an additional minimum slew time which depends on the observing mode. The slew to add can be retrieved from the messages at verbosity level-3 (see below), the parameter is "tSlewMin" and currently it is 6 seconds for the photometer AOTs and 19 seconds for the spectrometer ones.
For concatenated observations on the same target, which have no "Observatory overheads", then the "Observation completed time" is the "Total time".
This option gives the most basic information as shown in Figure 6.22.
Gives a simple breakdown of the total time for each block (detailing initialisation, PCAL flashes, BSM Moving, scanning and reconfiguration). An example is shown below:
This selection gives a more detailed breakdown with a running counter through the observation in seconds. This running counter, the number inside the square brackets in the example shown below, takes account of all overheads.
This selection gives even more detailed information about the observation, such as input values to the instrument commanding scripts, fixed values for some observation parameters, detailed list of individual commands sent to the instrument. An example of level-3 is shown below.
![[Note]](../../admonitions/note.png) | Note |
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In general, the information content in the different levels is not the same and it is possible to select multiple levels, for example levels 1+2+3 can be selected, however we advise using levels 1+3. |
It is obvious from the examples shown in the previous sections, that the details messages for levels above two contain a lot of verbose and too technical information. In some cases, however this is the only place where some additional information on the observation can be found. One such example is the minimum slew time which has to be added to the on source integration time and the instrument and observation overheads in order to get the observation complete time. This parameter can be found in level-3 messages as "tSlewMin" under "Pointing Mode Input Values".
For SPIRE Photometer Large Map mode:
The number of the scan lines in SPIRE Photometer Large Map mode;
The length of the scan line (longer than requested to make sure requested area is fully sampled);
The total integration time per scan line.
This information can be retrieved from the level-3 message as shown below for a large map of size 40x20 arcmin, cross-linked scan at nominal scan speed. Note that only the relevant values from the detailed message are shown and for some of them we insert a short description after the "#" sign.
# This is for the first scan direction (Scan angle A)
POF5 Observing Input values:
..nRepeats: 1
..mapWidth: 40.0 # in arcmin
..mapHeight: 20.0 # in arcmin
POF5 Fixed values:
..patt: 42.4 # this is the scan angle A in degrees
..d2: 348.0 # the distance between successive scan lines, in arcsec
..scanRate: 30.0 # in arcsec/s
Required number of scan lines in map: 4
Integration time per scan line: 98.7 # in seconds
Required scan length: 3081.0 # in arcsec
Total observing time: 412.0 # in seconds
# This is for the second scan direction (Scan angle B)
POF5 Observing Input values:
..nRepeats: 1
..mapWidth: 20.0 # in arcmin
..mapHeight: 40.0 # in arcmin
POF5 Fixed values:
..patt: 317.6 # this is the scan angle B in degrees
..d2: 348.0 # the distance between successive scan lines, in arcsec
..scanRate: 30.0 # in arcsec/s
Required number of scan lines in map: 8
Integration time per scan line: 58.7 # in seconds
Required scan length: 1881.0 # in arcsec, including turnaround
Total observing time: 504.0 # in seconds
From the above information we can see that the 40x20 arcmin large map will have 4 scan lines in one of the scan directions and 8 scan lines in the other. The scan length is 51.35 arcmin for the longer dimension and 31.35 arcmin for the shorter dimension, so overhead of 11.35 arcmin in all cases to make sure the requested area is fully sampled.
For SPIRE Spectrometer raster:
The number of raster positions and their position in the Y-Z plane relative to the target.
As before, this information can be retrieved from level-3 message as shown below for a spectrometer raster of size 4x6 arcmin, Medium spectral resolution and intermediate spatial sampling. Note that only some relevant values are shown.
Spectrometer Raster Observation
Observation Start
Uses observing mode SOF2_int
..Pointing: raster
..Sampling: intermediate # spatial sampling
..Resolution: M # spectral resolution - M=medium
..mapSize1: 4.0 # in arcmin
..mapSize2: 6.0 # in arcmin
..nRasters: 1
..nPoints: 12 # this is the number of rasters
..nMaps: 1
..nHCycles: 0
..nMCycles: 2 # two scans per raster
..nLCycles: 0
..Y raster positions:[-202.0244345422332,-119.9619345422332,...]
..Z raster positions:[32.64966536032054,114.65091536032054,...]