Changes

Mookodi time-stamp tests

518 bytes added, 13:36, 14 April 2022
/* Results */
[[File:mookodi_sat_pred_vs_source_pos.gif|frame|left|Figure1: Shown is an animated gif of 50 frames @ 2×2 binning, fast (5 MHz) readout rate, and 100ms exposure time per frame of an observation of a GNSS satellite moving through the FoV. Note the readout smear, which is particularly apparent for bright stars, due to the shutter set to the "ALWAYS OPEN" mode. '''NB. This mode is MANDATORY for continues fast imaging.''' Approximate time between each frame is ~400ms (i.e., ~300ms dead-time between each frame due to image readout time, header information collection + population into fits header, and file written to disk). The CCD is flushed to clear any charge collected on the chip during dead-time before next frame is taken. The blue circles show the auto-detection of sources and which are used for astrometric calibration. The red cross shows the predicted postion of the satellite at the header time (keyword=DATE-OBS) + half the exposure time (in this case 50us) by querying an independent external satellite database. The green cross shows the position of the auto-detected source extracted that is closest predicted postion]]
[[File:mookodi_delta_t_plot.png|frame|left|Figure2: Shown (a) Plotted in purple symbols is the offset in predicted vs. observed sky-coordinate of the GNSS satellite (i.e. the difference between the red and green cross location in Figure 1 above). It is about 2 arc-seconds for each frame which is close to the detectability limit at 2×2 binning which corresponds to a plate-scale of 1.2 arc-seconds/px (b) Plotted in orange symbols is the calculated time difference taking inot account the sky-rate of the partucalr satellite (in this case at this observed time 30.55 arc-seconds/s]]
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