Below are summarized the corrections which should be applied to the reported integration time (in the FITS headers of the images) in order to get the real on-sky integration time for each of the sofware versions of the SDSU controller.
Further inforrmation about the INGRID integration timing error associated to version 3.2 can be found here.
NOTE: There is not timing error with UltraDas (i.e. since 1st September 2001).
INGSWID = '3.2-3.2-3.1-3.1 ' / Detector Controller Software Identifier
INGRDTIM= 0.600 / Array Read Time (s)
EXPTIM = 8 / On-sky Exposure Time (secs)the corrected integration time is 8.264 s.
EXPTIM+(readout time-0.6s)*n+mux flush time,
where readout time=0.732s and mux flush time=0.132s.
INGSWID = '3.1-3.1-3.1-3.1 ' / Detector Controller Software Identifierand the reported readout time should be:
INGRDTIM= 0.600 / Array Read Time (s)
EXPTIM+0.150*n+0.146,
The exposure time as recorded in the FITS headers must be increased by 0.146 seconds only, independently of the number of non-destructive readouts (keyword INGNR) performed.
NOTE: The corrections above (for all
the 3 cases) do not depend on the number of coaverages performed
(keyword
INGNC in the FITS headers).
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