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Re: Mirrored Artificial Horizon
From: Geoffrey Kolbe
Date: 2003 Nov 2, 16:56 +0000
From: Geoffrey Kolbe
Date: 2003 Nov 2, 16:56 +0000
For those following this particular thread, I will just come back and defend my analysis of Kieran Kelly's problem, to which George took exception. George's analysis is quite correct, as far as it goes, but I think his analysis is too simplistic. He has taken a very particular scenario for the topology of the mirror, (which we do not know). When he says he has chosen dished or spherical shape, he has in fact analysed it as a cylindrical form. I think that if a weighted analysis was done over the possible topologies of the mirror, it would turn out in the end to be quite similar to the resolution analysis which I used. I think such an analysis would return a quite similar result in the order of 0.1 arc-minute for the mean angular deviation we should expect for a random 2cm diameter section of a mirror having diameter 14cm and flat to 7 wavelengths. I may be out by a factor of two or so, but I would be surprised if it was more than that. That said, George and I both agree that Kieran should not worry about the flatness of his mirror. Geoffrey Kolbe.