The PERL program mkskyflat1.pl will create a pair of OBs to take flat fields: 

 * the one starting with "SkyFlatTest..." will slew and obtain a strip to test counts. 
 * the one starting with "SkyFlat..." will slew and execute a 5-pt dither.

There are four options for input: 

The full syntax is:

./mkskyflat1.pl RA_hh RA_mm RA_ss DEC_dd DEC_mm DEC_ss PA Filter_Blue Filter_Red ExpTime_Blue ExpTime_Red

However, if the "standard" flat field position and exposure time scaling are requested, the coordinates
can be replaced with an "e" (evening "standard") or "m" (morning "standard") and no exposure times
need be given. For example, 

./mkskyflat1.pl e 0 U Y 

will create a pair of OBs at the evening "standard" position, 0 position angle, and using the U-BESSEL and Y-FAN filters
with appropriate exposure time scaling to yield similar counts in both channels.

The minimum exposure time is 1sec (can be decreased by changing the scale factor on the User Inferface) and
when the needed expsoure times differ by greater than a factor 3, a warning is issued, asking whether the user
would like to choose a different pair of filters (sometimes this may not be possible, e.g. for any combination which
includes the narrow band F972N20 filter).

The first letter of the desired filter is sufficient to specify the filter.
for LBC-Blue:
S = SDT_Uspec
U = U-BESSEL 
B = B-BESSEL 
V = V-BESSEL 
g = g-SLOAN
r = r-SLOAN

for LBC-Red:
V = V-BESSEL
R = R-BESSEL
I = I-BESSEL
r = r-SLOAN 
i = i-SLOAN 
z = z-SLOAN 
Y = Y-FAN  
F = F972N20

The "standard" flat field position is:
RA = LST at sunset/sunrise minus 15 minutes, and 
DEC = 27 degrees. 

mkskyflat1.pl uses the program 'skycalc' by John Thorstensen to determine
the LST at sunset or sunrise on the current date. This syntax is to be used
on the date (or within a few days) that the created flat field OBs will be run.

The syntax is:

./mkskyflat1.pl [e|m] PA Filter_Blue Filter_Red ExpTime_Blue ExpTime_Red

where a single letter indicates whether these OBs are to be used to take 
evening("e") or morning("m") flats.