Telescope Size for Binoviewers

Started by kmtmd, 11/20/2004 09:04PM
Posted 11/20/2004 09:04PM | Edited 11/20/2004 09:05PM Opening Post
Is there a minimum size that a telescope neeeds to be to use a binoviewer (e.g. could I use one with my C90)? Also is there a difference in minimum telescope size for a 1.25" vs. 2" binoviewer?

Thanks,

Kate
Posted 11/20/2004 10:07PM #1
Hi Kate,
On Jupiter, Saturn, the moon and the sun, a binoviewer on the c90 would be fine. I haven't used one myself, but I used a binoviewer on my 80mm refractor and have heard of them on 76mm refractors. Deep sky objects would be out, except for maybe the brightest of open clusters, but you probably knew this anyway.
I don't think there is any difference in size of telescope needed for a 2" vs. a 1.25" binoviewer, but the only 2" model is made by Harry Siebert and is really for Harry Siebert fans only. I wouldn't recommend one of those contraptions on any size telescope. Hope this helps.
Nils
Posted 11/20/2004 10:56PM | Edited 11/21/2004 07:33AM #2
Hi Kate,

I have used my 1.25 Black Nights on a 70mm Skywatcher Refractor and on my ETX-90.

To use a 2" binoviewer you would need a telescope with a two inch focuser. In the case of an SCT like your C90 you would need at least a two inch visual back.

I think for use with a C90 the better choice would be the 1.25 Black Night binoviewers or the new Burgess binoviewers. I understand they are selling for $199. That's a hard price to beat.

BTW, The 2" Siebert binoviewer is not a contraption, it is a very well made 2" compliment to the smaller 1.25 Black Night units. The 2" Siebert Elite is the most advanced binoviewer on the market today.

I have enclosed a photo of the two units side by side. On the right is a standard Black Night unit. On the left is a 2" 45mm Black Night Elite.


I replaced the image with one using a camera tripod and no flash. This is a truer image of both units appearance.

Don Durbin




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