Yesterday I finished sculpting the primary mirror and that means all the optics are done.
Figuring an f/2.7 mirror is quite an adventure. I did most of it guided by a Ross Null setup and when it became difficult to make more progress, I switched to the Bath interferometer. At that point I was within one lambda wavefront error but it was a long road from there to 0.035 lambda rms.
The attached report is based on only 5 noisy interferograms taken at 72 degree rotation so the mirror is probably better than the report indicates as air currents, vibrations and other artefacts have not been properly averaged out.
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