Quote:
Originally Posted by JJDOBBER79
Thanks Renato, you certainly have some gear (20 pairs????)
I think I am going to give the andrews bino a go as an entry level, can't go wrong with $90. I can get some cheap Denks etc on astromart but would cost $100 to get them here. I still don't know what I need to get it to work, would a different focuser be an option and if so, what would that mean for single ep viewing?
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Make sure you ask the knowledgeable people at Andrews if their binoviewer works in a dob, and if not, if they have the accessory that makes it do so.
On my Denkmeir binoviewer, I have to connect the optical correction piece, the Newtonian spacer and the nose piece together and into the binoviewer to be able to get focus. It's a long light relay mechanism. I don't think a different focuser would get you there if your telescope was like mine.
If your secondary mirror isn't somewhat oversized, and it currently exactly matches the light coming in from the primary mirror, wouldn't raising the primary mirror to get focus in a binoviewer effectively reduce the aperture of your telescope? Since some of the light from the primary would not be reflected by the secondary?
Before buying any cheap Denks on Astromart, you have to make sure that you know what you are buying. I bought the package with everything in it which cost the most, but at the time they did sell lesser packages. So you may be buying something that was cheaper in the first instance. I've got the older type Denkmeir (I think they have Type 11 now), and in a Newtonian I can get 1.3X and 2.3X with any set of eyepieces. By way of contrast, in an SCT I can get 0.66X, 1.15X and 2X.
As for my binoculars, some are expensive, some are moderately price and some are Ebay bargains. Funniest pair I bought was three years ago when I bid $51 on a pair of brand new Sakura 20X80 binoculars and won. Comparing them to my other binoculars, they were actually 16X75 in performance, and they had that looking down a well effect, like looking through orthoscopic eyepieces. But they are very good on DSOs. I told club members about them, and one guy won a pair for $46, and he was delighted with them.
Cheers,
Renato
