Troubleshooting guide

Appendix 4: Additional Notes on MOS Plates
An example MOS plate for use at the 4-m is shown adjacent, in Figure 4. It
is approximately full size (~105 mm in length).
The sizes of the slits and alignment boxes are the same size in pixels for both
telescopes.
The slitlets are 3 pixels (0.9" at the 4-m) wide, with a minimum length of
approximately 30 to 40 pixels (9" to 12" at the 4-m).
The alignment boxes are 25 to 30 pixels (7.5" to 9" at the 4-m) on a side.
We usually try to find guide stars with K magnitudes in the range 11–13.
The view of the MOS wheel, from the side that will be seen when loading is presented on the next page. Copy
or download and print it ( http://flamingos.astro.ufl.edu/Manuals/), and then annotate it as you
load the plates.
Critical annotation items include (see Figure 3):
Plate name or ID
Rotator Position Angle for proper plate orientation on the sky
Slit Width, in pixels
Compass, with sky parity showing the orientation of North and East
After the wheel is back in the MOS dewar, and the dewar is on the pump, run the script
set.new.mos.plate.names.pl, so that the plate name makes it into the FITS header when the plate is
selected.
FLAMINGOS@4-m, Ver. 2.34, 2006 Apr 04 Page 43 of 44
Figure 4—Example MOSplate.