Observatory Policy for Machining IMACS Slit Masks


All slit mask files must be submitted at least 6 weeks in advance of an observing run.


Frank Perez must give permission for files to be submitted between 3-6 weeks before a run. We cannot guarantee that masks will be cut in this interval.


NO masks will be cut less than 3 weeks before the deadline.



The following summarizes the FAILURE rate of meeting the old policy (submitting mask files at least 28 days in advance).


Arizona     66% (100 of 151 files)
Carnegie 87% (103 of 118 files)
Chile 86% (12 of 14 files)
CfA 79% (59 of 75 files)
MIT 74% (29 of 39 files)
Michigan 47% (17 of 36 files)
Toronto 98% (44 of 45 files)


In addition to this policy, observers should always verify that their program has the correct f/ratio (IMACS/2 or IMACS/4) for their program. The Observatory works hard to block schedule IMACS to avoid frequent changes between f/ratios.