Setup with LRS2
Minimum exposure times are 15 seconds. It is advised that the PI stay above this value as there is some small uncertainty in the shutter timings at the present time.
Setups times are typically less than 10 minutes for all targets. For targets fainter than the ACQ camera can image (~20.5) we will find setup stars within the ACQ camera field of view for setup, we call this mode a blind setup. A blind setup also applies if you have specified a visible point source to not be at the center of the IFU. If you know that you will need a blind setup it is good to note that in the target notes in TSL.
Readout time is about 40 seconds, which also is the amount of time that it takes to move from LRS2-B to LRS2-R. NOTE: the Act of moving between LRS2-B and LRS2-R can introduce a few arcseconds of mis-centering. Setup images taken with the ACAM camera will be taken just once final positioning and guiding are achieved but before final focus has been achieved. These images are saved automatically (see XXXX for more details about the location of these files). If, for your science case, final focus must be achieved before your exposure is started this should be noted in your TSL target notes as well.
It is possible, if the requested exposures are short enough, to request that targets be observed with both LRS2-B and LRS2-R in the same trajectory. Usually setup times are less than 1 minute to offset between these two positions. The PI should request that the targets be grouped with type "SEQ" and a group name that is unique .
Last updated: Thu, 23 Nov 2017 15:05:56 -0600 shetrone