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Re: How does the AstraIIIb split mirror work?
From: Ken Muldrew
Date: 2004 Apr 25, 22:19 -0600
From: Ken Muldrew
Date: 2004 Apr 25, 22:19 -0600
Ken Muldrew wrote: > When the telescope is centered, and the sextant is rotated so that > half the sun vanishes, removal of the paper does not affect the image > whatsoever. I just did this with the moon, with no shades or anything to interfere with the image, and I now see what you see. When the paper is removed from the glass, there is a reflection that is as bright, or nearly so, as that coming from the mirror. I don't know why it didn't work with the sun, but I think it was due to an error on my part. The reflection past the middle of the field of view is a combined image from both the mirror and the glass until the object is rotated past the point where the scope can no longer get reflected light from the mirror. Then the image comes solely from reflection off the two glass surfaces. The transition is imperceptable with a 5x scope. George Huxtable was entirely correct in this matter and I thank him for sticking with it until I was able to understand the phenomenon. Ken Muldrew.
