Thread: Finder Scope
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Old 03-11-2021, 05:55 AM
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Eldest_Sibling (Alan)
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Join Date: May 2017
Location: Mid-South, U.S.
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Ah, rotation...

Thank you, Jeff, for explaining all of that. That of my lone apochromat is indexed, and in the past I have wondered as to those of achromats. I imagine that they might benefit from that as well. But do most, if not all, bother with that of achromats? In testing varying thicknesses of spacers, I have reduced the flaring, considerably.

I would love, dearly, to remove every last trace. I am not seeing any flaring now, at 25x and higher.

Then, it is not entertaining to me at all to watch Jupiter transiting across the field-of-view at 9.4x, with a 32mm Plossl; so very small they are, and my 32mm is not a Tele Vue. I do have a Tele Vue 40mm Plossl, and purchased when I didn't know any better. The view through both simply does not do it for me. Until most recently, I have preferred medium-to-high powers, particularly those highest, and possible per a given aperture. However, I'm going to give the lower powers a bit more "love", and with a 102mm f/5.9 achromat I purchased recently.

Although, getting back to the 70/300, I do get a bit giddier at 15x with a 20mm, and the flaring does seems less obtrusive, but it's still present.

This, a best simulation of what I saw, at 9.4x...

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I will be researching indexing further. I could prevent the elements from rotating in future, once a sweet-spot is found. Thank you again.
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