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Re: How does the AstraIIIb split mirror work?
From: Jim Thompson
Date: 2004 Apr 24, 09:04 -0300
From: Jim Thompson
Date: 2004 Apr 24, 09:04 -0300
I repeated the experiment, this time blocking the horizon mirror's clear window from the front. Not surprisingly I guess, for all 3 sighting devices (sight tube, 4.5x30 and 6x40 telescopes) I only saw the index mirror's image in the right half of the field of view, and it stopped sharply at the center of the field of view where the vertical edge of the mirror ended. For what it's worth, I again blocked the clear window from behind and studied the slightly dimmer index mirror's image that showed past the center line in the left half of the field of view. I could only perceive a single image reflecting from the clear window, but I don't know how precise that would be. I don't know whether I could pick up two images (one from the front of the horizon glass and one from the back) with the resolution of my biophysical optics, if in fact there are two images spaced very slightly apart vertically in the left field of view. I was looking at a series of horizontal black electric lines against blue sky about 200 yards away, using the 6x30 telescope. Jim Thompson jim2@jimthompson.net www.jimthompson.net Outgoing mail scanned by Norton Antivirus -----------------------------------------