Mimir - Pupil Viewer Images Pre, Post Instrument Tilt Shimming
The Mimir Pupil Viewer Mode was used to identify the sense and amount of instrument tilt that needed to be introduced to put the telescope optical axis along the Mimir instrument optical axis. The first image below shows the pupil view of the not-quite-aligned telescope image and Mimir pupil mask.
The second image (below) shows how the pupil looked after introducing a 0.015" thick steel shim under the washer surrounding the south-east mounting bolt. The image is now highly symmetric.
Tests conducted by pointing the telescope at zenith, then 4 hours over in each of the four cardinal directions showed pupil motion due to the instrument to be at or below about 0.001-0.002" (one or two detector pixels).
Finally, a series of PV images were obtained, each with a small camera offset. These images were coadded with median filtering to remove the bad pixels, resulting in the final PV image below.