. . . of 20080331, viz:

           (x0  y0  x'  y') = (-0.1   -1.2   -0.5    0.9 )

We have again performed RA/Dec jiggle maps of point-like targets sandwiched bewteen AZ/EL fivepoints, and record the results as before:

                                             IMG_ANG    (uaz,uel)     (uaz,uel)
     UT    #  target    az el    daz   del   obs calc     before    after-before
                                                          after
20080424  19    CIT6   312 73   +2.4  -0.8       -53    -0.7  +7.9 
                                                 +37    -0.4  +8.8   +0.3  +0.9

20080424  22   APLyn   329 25   -0.9  -2.4       -69    -0.0  +7.9
                                                 +21    +2.1  +9.0   +2.2  +1.1

20080424  25    UHya   208 53   +3.9  -1.1       +26    +1.9  +5.2
                                                        +2.5  +5.3   +0.6  +0.1

20080424  28   RXBoo    73 57   +3.2  -6.3       -30    +0.1  +4.8
                                                        +3.2  -3.7   +3.1  -8.5

20080424  32    XHer    44 38   +2.7  -0.8       -39    +4.4  -1.7
                                                        +5.8  -2.0   +1.4  -0.3

20080424  36 irc+10216 268 46   +0.9  +0.7       -29    +4.9  -0.4
                                                 +61    +3.3  -0.6   -0.6  -0.2

20080426  28  CRL2688  410 60   +1.6  -8.1  -94  -94    +0.8  +1.7
                                                  -4    +1.0  +4.0   +0.2  +2.3

20080426  32   RXBoo   291 20   +0.5  -3.7  -57  -57    +4.7  +1.9
                                                 +33    +4.2  -0.8   -0.5  -2.7
                                                        
20080426  37   RCas    400 34   +1.8  -0.1  -45  -45    +1.9  -3.5
                                                        +2.9  -4.0   +1.0  -0.5

20080427  53   GL1922  193 44   +1.6  -0.4  +31  +31    +4.6  +5.4
                                                        +1.1  +4.7   -3.5  -0.7

20080428  24 irc+10216 263 57   -0.8  +0.9  +74  +74    +2.8  +4.9
                                                 -16    +3.1  +5.1   +0.3  +0.2
                                                        

                               ------------   
               N=11  Mean       +1.5  -2.0
                     s.d.        1.5   2.7

         cf    N=38  Mean       -0.3  -0.0   without the model
                     s.d.        2.0   2.5

All-sky pointing
Some 'All-sky' pointing data were recorded with and without the K-mirror model in place:

      UT      K-mirror model    No.     CA  +-  dS       IE  +-  dZ

   20080424        NO           10    +15.8 +- 2.1     +32.4 +- 4.1
   20080424       YES           28    +16.2 +- 1.7     +34.6 +- 3.8

Both subsets of HARP data seem considerably worse in their elevation performance when compared with the HARP data taken in the nights before and after, so the relative performance is perhaps more meaningful than the absolute rms errors.

Conclusions
Improvement in the azimuth performance perhaps, but not in elevation. Although - if one were being optimistic - the elevation measures from the RA/DEC maps are dominated by two exceedingly large negative measures - and perhaps further data will reveal their deviance.