C11 Mechanical Alignment & Collimation
Before and After Pictures
These pictures were taken in the same conditions with the same camera at the same temperature. You can see that the effect of de-centering the corrector has a dramatic effect in star shapes and overall sharpness of focus.
The issue with the scope initially was a mechanical issue. The baffle tube wasn't square to the primary cell casting. So the primary being square to the baffle tube ended up not being co-axial with the secondary or corrector. The corrector was shifted to one side of the corrector cell and shimmed to be tilted a bit to compensate. This was obviously a compromise and the field of this scope never looked good...
The problem became even more apparent when I purchased an Hyperstar. It then made a lot of sense to be able to tilt the primary so I could re-center the corrector. My thinking was that if the field was ok with the hyperstar then it would improve at prime focus too because the secondary axis should be in line with the primary axis as well.
*note:This section will be updated as I collect more test data. - Updated March 6, 2013
- 2013-03-02: Star tests performed with artificial star on a bench. Test #1, Test #2, Test #3
- 2013-03-06: Star tests performed on Canopus and Achernar.
- 2013-03-06: 3x10s unguided, prime focus (F/10) on Orion Sword - (SONY NEX-5) full frame uncropped - no flattener.
- 2013-03-06: Jupiter & its moons, prime focus (F/10) - (SONY NEX-5) full frame uncropped - no flattener.
