Giles' checks of the results of John's analysis of grid-test data

May 17, 2006

***********************************************************************
Phi_sky_m is "Phi_sky_measured" from John's recent E-mail to me.  He
put five grid tests through the sharpinteg-sharpcombine pipeline 
and obtained the values of Phi_sky_m given below. 

The other data comes from the observing log, as summarized in my March 26
memo on the analysis log.  The letters identifying each grid test come
from that same memo.

Phi_sky_c is "Phi_sky_calculated" by which I mean calculated using the
formula <<< Phi_sky = -Phi_inst_cor + EL + PAR >>> that is given in my
memo on sign and angle conventions (analysis log, April 13th).

Note that for grid test J, the parallactic angle was not recorded in my
notes that are posted on the analysis logbook, presumably because it was
changing too fast to be reliable.

***********************************************************************
test    Phi_sky_m  EL    PAR     wires   Phi_inst_cor    Phi_sky_c   error     

C        132       55   -10      Vert       90          -45 (=135)    -3
G        137       80   -80      45 CW      45          -45 (=135)    +2
H        137       80   -80      45 CW      45          -45 (=135)    +2
J        103       90    ?       Vert       90               ?         ? 
K        103       50   -40      Vert       90          -80 (=100)    +3
***********************************************************************