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BV internal reflections ?

Started by progenitor, 07/04/2005 07:36PM
Posted 07/04/2005 07:36PM Opening Post
I had the first opportunity to use the Burgess bino with Siebert 1.6x adapter and stock 20mm EP yesterday after sorting out the setup problems (reversion to shorter original Vixen 2" focuser tube adapter helped).
I think I am getting hooked on binoviewing.
There was one annoyance: scrolling the sky, at times there was a "star" of noticeable "magnitude" traveling across the field at different speed and trajectory than the star "background". Of course it was dependent on the direction of the scope move. What it could be, a reflection somewhere ?
Also, how can I measure in some simple way what effective mag. factor I am getting ?
Posted 07/05/2005 04:04AM #1

You can measure magnification by using a single eyepiece focused on a yardstick an appropriate distance away. Then use the same eyepiece in the binoviewer with the corrector.

If you have a refractor you may find that you can focus on a terrestrial object (Like a yardstick) by going straight into the focuser without an adapter. You can then add the adapter and do the math.

There is also a third way using a star and a graduated eyepiece. Kill the tracking drive and allow the star to cross a fixed distance in the eyepiece and compare with the eyepiece in the binoviewer with the corrector. (Hint.. Don't use Polaris wink )