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Is 1.2x really 1.2x ?

Started by Brian Goodman, 02/12/2004 11:52AM
Posted 02/12/2004 11:52AM Opening Post
Hi guy's. I,ve been fooling around with my 1.25 inch Refractor OCS trying to determine my lowest power. I,ve compared my Binoviewer and refractors with various Binoculars and i've concluded that i'm getting higher powers than I should following the 1.2x rule. I figure that 1.4x or even higher is closer to what i'm seeing . Has anyone else sensed this or am I messing up somewhere in my calculations?
Posted 02/12/2004 12:23PM #1
Nope, your math is fine.See Tom Holes post,copied here in it's entirety,Re: .3 magnitude equals what ?
Posted by Tom Hole on 12/22/2003 6:56:04 PM

Glen,

I can't put a mag figure on the difference. My test was one night with my Denk stds with the 2" OCS and the TV binovues with the TV 2x corrector. Used 2 GTO zoom ep's. The target was M57. There was a star just above M57 (below in the ep) that was right on the limit of my vision with the Televues. It required averted vision to detect in the TV's. But with the Denks at the same magnification, it was visible with direct vision. Not easily visible, but visible with direct vision. This led me to comment on the Denks stds with 2" OCS going a bit deeper than the TV binovues with 2x corrector. I do not have any idea what mag difference that might be.

I'm sure this test was rife with potential errors. Mismatched mags (I was using a pair of zoom ep's) could have easily made the difference. I had measured the actual magnification of the Denks with the 2" OCS and the Binovues with the 2x corrector during the day. The Denks/2" OCS were actually 1.37x mag. The TV was 2x. So I felt very comfortable selecting a zoom setting, but who knows how accurate the markings on the zoom were.

The folks that can really nail this down are the SCT users. Correctorless binoviewer testing is a good basis for data with respect to the binoviewers themselves. Testing on a newt with a corrector at potentially differenct mags introduces a lot of variables that are difficult, if not impssible, to isolate.

So, that's my data. Can't explain it. Don't need to, really since I still have both of them. Maybe if I sell one, the other one will suddenly start getting grander laurels wink

Clear skies,

Tom