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    Re: Davis and Astra head to head
    From: Randall Morrow
    Date: 2013 Mar 4, 09:15 -0800

    My Davis is a Mark 15 that is close to 30 years old. Most of it's life was spent on my closet shelf until recently. The backlsh issue had occurred to me so the star "superimposing images" IC checks were done in pairs, one turning onto the arc and theother turning off, without releasing the index arm. This was done three time in order average out backlash as you suggested. The sun correction were also done turning the micrometer in only one dorection. It occurred to me after reading your note that all the sights were taken in a series as the sun rose toward noon. The screw was always turned in one direction. That might have been seen in all the sights being "away". My suspicion that it was a personal bias in viewing was based on the same "away" trend in the Astra sights. I will try another set of these after noon next week end to see if all the "aways" change to "towards". Thank you for your insights.
    Regards, Randy

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