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    Suryaputhra's Avatar
    Suryaputhra is offline White Dwarf
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    Question What exactly those rectangular shadows in defused star test.

    I have recently collimated my Orion SpaceProbe 130 EQ Reflector Telescope. Spider vanes are equal in length, secondary mirror correctly centered to focuser tube and tilt. Completed correct coliimation. When I have done star test surprisingly there are rectangular shadows appearing at 5 o'clock and 11 o'clock position. I believe the 11' o'clock is focuser draw tube and the the other is secondary mirror clip. I could not take picture of it but could able to find picture of similar issue someone faced. Please look in the issue and guide me. Actually there is a photo with shadows but some reason I can not upload it. The shadows exactly protrude at 11 and 5 o'clock positions in the image attached.
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    rocdoc's Avatar
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    Default Re: What exactly those rectangular shadows in defused star test.

    There is another one at 3 o’clock. I think those are the clips holding the primary in place by its edges.
    Properly collimated cornea-lens-vitreous optical apparatus, projecting on retinal sensor slightly limited by deuteranomaly, feeding through stock optic nerves into functional primary cortex, processed through frequently misfiring and buggy integrative cortex.
    Other instruments: Skyline 8" Dobsonian; Celestron Omni XLT 120 w upgraded focuser and diagonal on Stellarvue M2C mount; Oberwerk 25x100 IF; Celestron SkyMaster 8x56. Main EPs: ES 82º 24mm and 11mm, Celestron Luminos 19mm, Meade UWA 14mm, Meade HD-60 6.5mm. Filters: UHC, 13%, blue. Finders: RACI, Telrad, RDF, reticle.



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