Author: Mackenzie Boyd
Date:   July 19th, 2010

There are several versions of the voyager camera kernel files, this file should
explain the differences and the reasons for the differences.
The original camera kernels, acquired from the Isis2 data area, are:
vg1_jup_qmw_wa.bc
vg1_jup_qmw_na.bc
vg1_sat_qmw_wa.bc
vg1_sat_qmw_na.bc

These files did not have the correct frame codes to match more resent kernels.
The frame kernel has a date and description of this change which involved
subtracting 100 from all scan platform instrument ID codes. The update changed
the frame codes from -31001 and -31002 to -31101 and -31102. The pointing for
the NARROW_ANGLE_CAMERA is the same as the SCAN_PLATFORM and the pointing for 
the WIDE_ANGLE_CAMERA has a small rotation away from the SCAN_PLATFORM. Two
changes were made to the kernels to get to the following files. Those changes
were, 1, change the frame code from -31001 and -31002 to -31100, the
SCAN_PLATFORM code, and 2, for the WIDE_ANGLE_CAMERA only, remove the rotation
included in the files. The files are then all SCAN_PLATFORM pointing with
frame code -31100.
The updated frame code kernels are:
vg1_jup_qmw_na_fc-31100.bc
vg1_jup_qmw_wa_fc-31100.bc
vg1_sat_qmw_na_fc-31100.bc
vg1_sat_qmw_wa_fc-31100.bc

Finally, the kernels were type 1, discrete pointing. For Isis3 continuous
pointing, type 2, is necessary. The utility used to change the type was
ckspanit, with a tolerance of 800. The final kernels that are usable in Isis3
are:
vg1_jup_qmw_na_fc-31100_t2.bc
vg1_jup_qmw_wa_fc-31100_t2.bc
vg1_sat_qmw_na_fc-31100_t2.bc
vg1_sat_qmw_wa_fc-31100_t2.bc

The other files contained in this directory are from
http://pds-rings.seti.org/voyager/spice/ck.html and are supposed to be
superior to the files from Isis2, they can be read about in their matching
text files. Type 2 versions of these files have been made so that they can be
used in Isis3.