We have downloaded about 10 MB of engineering telemetry from the first two ST-16RT2 star trackers on-orbit, and it looks amazing. Successful quaternion generation rate is in excess of 99.9%. The overall angular error is half that of the previous generation ST-16.
Both the ST-16 and ST-16RT2 have the same basic optical parameters: 16 mm focal length, 10 mm entry pupil. The difference is that the ST-16 uses an industrial video lens, while the ST-16RT2 uses a full custom lens that we designed from scratch. The electronics and software are identical between the two. Designing and manufacturing this new lens was incredibly expensive and painful, and we often wondered whether it was worthwhile. We can say now that yes, it absolutely was.