Abort options on the MOSFIRE exposure control gui are all tested and function as expected. Once an exposure is started, the abort dropdown list becomes selectable. Below is an image of the exposure control gui with the dropdown list revealed during a 200s dark exposure.

The exposure control gui has several options and below we describe more details on the abort options.

• Abort After Frame This aborts after completing the current exposure that is in progress. If you were in the middle of a sequence of exposures, the exposure in progress will be saved, but the rest of the sequence will not be executed. If in the middle of a dither sequence, the telescope returns to the base pointing after the current exposure finishes. Default Behavior.
• Abort Immediately Interrupt the current exposure immediately. Data saved will be corrupt.
• Abort After Read Abort after read will abort following the next read of the data. If in MCDS mode, the abort will follow the next read either at the beginning of the exposure or at the end of the exposure. Example: if MCDS 8 is set and you are in the middle of a 120 sec exposure, the abort after read will abort near the end of the exposure following the first of the 8 reads.
• Abort After Group This is not used for MCDS mode. Only UTR mode and aborts after a set of reads in the middle of exposures. For typical observing sequences, this option should be ignored.
• Abort After Coadd Aborts after the Coadd is complete. This will read the current coadd and then abort. Data is saved, but will not have the full coadds.
• Abort After Repeat Aborts after the current dither pattern completes. If using a mask nod dither pattern, the abort will halt the exposure process after data is acquired at both dither positions. The telescope returns to the base pointing following completion of the dither pattern.