Large Binocular Cameras
EF Analysis
2009 09 04 Tests of EF analysis of LBCR/B images
LBC/EF Comparison for 2009 09 04 Comparison of EF and LBCFPIA results
FPIA Z4 Calibration Calibration of Z4
FPIA Z11 Calibration Calibration of Z11 based on data from 20091023
UPdated FPIA Z11 Calibration Updated Z11 results from data from 20091023
FPIA Z22 Calibration Calibration of Z22 based on data from 20091023
FPIA Calibration with Big 100 pixel pupils Calibration of Z11, Z22, Z5, Z7, Z4 with ~100 pixel pupils. Data from 20091023
The results of FPIA in the above links were computed with the same configuration file that is used for
dofpia. The values of SphOffset and SphRedCorrection were set so that convergence would be reached for a pupil to which some spherical aberration was added to make the inner hole larger and easier for FPIA to measure. This spherical aberration is removed after the last iteration. So in
dofpia, convergence is to a pupil with an inner hole to outer diameter ratio = 0.2 (Blue); this spherical, Z11, and the corresponding defocus, Z4 = 1.9* Z11 are estimated and added to whatever lbcfpia computes on the last pupil image in the iterative
dofpia routine.
However, to obtain accurate results for Z4 and Z11 for these extra/intra focal pairs which were taken outside of
dofpia, the equation for the Z11 computation needed to be edited, so that the convergence would be to a pupil with no Z11 added. Ideally convergence should be to the expected dimensions for a star 0.8mm out of focus. However, the measured values for these out of focus stars are not in exact agreement with the model, and instead the values we assumed in editing this equation were determined by measuring two sets of collimated pupils: blue pupils lbcb.20091023.082418 and 082751 and red pupils lbcb.20091023.082413 and 082744. Although the red pupils were smaller on both images, we took the nominal value 62.4, which is determined by the value of alpha = 78, for both blue and red. We assumed different ratios for the inner hole to outer diameter for blue and red.
The original values for the ratios (inner hole/outer diameter) and outer diameters, and for the parameters, SphOffset, SphRedCorrection
are listed in the table below as well as the edited values for running the code outside of
dofpia.
channel 
original 




modified 





Inner/Outer 
Outer D 
SphOffset 
SphRedCorrection 
alpha 
Inner/Outer 
Outer D 
SphOffset 
SphRedCorrection 
alpha 
Blue 
0.200 
62.5 
88 

78 
0.16 
62.5 
396 

78 
Red 
0.219 
58 
88 
225 
78 
0.20 
58 
396 
484 
78 
Results for the two sets of collimated pupils with the original and with the modified parameters:
original 

channel 
filename 
Z4 
Z5 
Z6 
Z7 
Z8 
Z11 
Z22 
Blue 
lbcb.20091023.082418.fits[2] 
1351.11 
3.21135 
163.942 
53.0878 
10.4714 
667.978 
43.4787 
Blue 
lbcb.20091023.082751.fits[2] 
835.717 
141.237 
277.569 
97.3532 
49.2375 
544.321 
73.7577 
Red 
lbcr.20091023.082413.fits[2] 
380.742 
34.3555 
266.133 
3.35116 
119.541 
201.352 
12.0603 
Red 
lbcr.20091023.082744.fits[2] 
521.220 
11.5798 
249.260 
141.456 
163.700 
314.306 
0.349864 
modified 

channel 
filename 
Z4 
Z5 
Z6 
Z7 
Z8 
Z11 
Z22 
Blue 
lbcb.20091023.082418.fits[2] 
247.595 
3.21135 
163.942 
53.0878 
10.4714 
87.1777 
43.4787 
Blue 
lbcb.20091023.082751.fits[2] 
267.803 
141.237 
277.569 
97.3532 
49.2375 
36.4792 
73.7577 
Red 
lbcr.20091023.082413.fits[2] 
230.679 
34.3555 
266.133 
3.35116 
119.541 
120.448 
12.0603 
Red 
lbcr.20091023.082744.fits[2] 
90.1999 
11.5798 
249.260 
141.456 
163.700 
7.49356 
0.349864 
FPIA Z11 modified for use outside of dofpia Z11 results modified for use outside of
dofpia, i.e. for convergence to a pupil with no spherical aberration. From data from 20091023
FPIA Z22 modified for use outside of dofpia Z22 results modified for use outside of
dofpia, i.e. for convergence to a pupil with no spherical aberration. From data from 20091023

DougMiller  08 Oct 2009