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I finished figuring the primary today. Unfortunately I got a bit over confident about airborne dust and ignored the north wind as I did some of the figuring.
As a result I ended up with a couple of scratches, which is very annoying although it won't affect the performance.
It was interesting to see how much easier it is to figure an f/3.7 mirror versus an f/2.7, as in the CDK. The interferograms are much easier to capture as the interferometer is not pushed to it's limit, and the processing of the interferograms is also easier.
The attached screenshot is a bit of a cheat because it shows only the spherical terms of the Zernike polynomials. If I enable all terms the Strehl ratio drops to 0.95 but it is way past the diffraction limit anyway.
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