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I couldn't help noticing the 7 zone foucault test claiming an 0.99 Strehl ratio. Such tests are useful for small slower mirrors but in larger fast mirrors are often idealized in relation to the reality as measuring the all important edge zones edge zones is much harder this way and of course complex figure distortions ( not just simple astigmatism ) more common with large fast and laminated mirrors are pretty much invisible to the maker using these methods. Do trust your eyes and star test diligently before making decisions on the optical quality.
I found the 16" F4 Fullham sandwich mirror I tested that was mentioned earlier in this thread , looked at with sensitive null interferometry to have results nothing like the documents presented here though I didn't see original foucault test results it was supplied with . I do wish you the best results with your new optics and as always trust your eyes.
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