CASPER identifies each instrument field of view (FOV) by a unique numerical code.  This code is used within CASPER to identify which FOV is being drawn on the graphic, and is also used to identify which spacecraft axis is being used to specify spacecraft orientation within a module.  For example, some ORS modules require pointing with the ORS boresight which is aligned with the spacecraft -Y axis.  CASPER defines the ISS NAC pixel to be exactly along this axis, and it is the pointing axis for ORS modules.  The numerical values of the pointing_axis and secondary_axis parameters that are saved to the CASPER Output file correspond to the following instrument FOVs.  Primary spacecraft axes are also indicated by negative numbers.

-6    Spacecraft -Z axis
-5    Spacecraft -Y axis
-4    Spacecraft -X axis
-3    Spacecraft +Z axis
-2    Spacecraft +Y axis
-1    Spacecraft +X axis
0    UVIS FUV Occultation slit
1    UVIS EUV Occultation slit
2    UVIS EUV Low resolution slit
3    UVIS EUV High resolution slit
4    UVIS FUV Low resolution slit
5    UVIS FUV High resolution slit
6    UVIS High Speed Photometer
7    UVIS Hydrogen-Deuterium Absorption Cell
8    UVIS EUV Solar occultation port
9    ISS Narrow angle camera
10    ISS Wide angle camera
11    VIMS "Full" FOV
12    VIMS "Half" FOV
13    VIMS 3/16 FOV
14    CIRS FP1 FOV
15    CIRS FP3 FOV
16    CIRS FP4 FOV
17    ISS Narrow angle camera pixel
18    ISS Wide angle camera pixel
19    VIMS FOV pixel
20    RSS X band half power ellipse
21    RSS KA band half power ellipse
22    RSS KU band half power ellipse
23    RSS S band half power ellipse
24    RSS Low Gain Antenna number 1
25    RSS Low Gain Antenna number 2
26    Cosmic Dust Analyzer
27    CAPS IMS
28    CAPS IBS
29    CAPS ELS
30    Langmuir Probe
31    Magnetometer boom
32    RPWS
33    INMS Open source
34    INMS Closed source
35    MAG sensor 1
36    MAG sensor 2
37    MIMI INCA
38    MIMI LEMMS 1
39    MIMI LEMMS 2
40    MIMI CHEMS
41    RADAR Beam 1 half power ellipse
42    RADAR Beam 2 half power ellipse
43    RADAR Beam 3 half power ellipse
44    RADAR Beam 4 half power ellipse
45    RADAR Beam 5 half power ellipse
46    VIMS X line scan
47    VIMS Z line scan
48    Galileo SSI Camera
49    Galileo SSI Pixel
50    VIMS Solar Port