finding owners of giant binoculars

Started by Pol-Aris, 06/28/2008 08:36PM
Posted 06/28/2008 08:36PM Opening Post
After more than 50 years in amateur astronomy, I have yet to run across anyone with giant binoculars in the 120-150mm range. Admittedly, I haven't been to any of the national star parties, but one would think that in all those years I would have come across someone in either southeastern Wisconsin or northeastern Illinois who could have treated me to a view through one of these giants. Right now I own 4 telescopes and have built several, but my desire has always been to posess very large astronomical binoculars. However, I am leery of spending possibly several thousand dollars on a class of instrument I have never looked through. Is there anyone out there, in my part of the world, who might be able to help??? Thank you.
Posted 06/29/2008 04:00AM #1
I've been assembling the components for a giant binocular for a couple of years (as time/money permits)- 2 F/8 Celestron CR6 refractors, a strong tripod with a center column that can extend to over 7 feet. Now I need to put together the bits and pieces- large mirrors/diagonals, etc.

I'm playing with the option of using oversided focal reducers to get wider views. When all said and done the project should run less than $1000 total. It won't be the prettiest thing, and I hope it all works.

Jess Tauber
Posted 07/01/2008 02:38PM #2
Hi Aris -- I have a pair of Nikon 20x120's -- bought them about a year ago. I haven't found a lot of user feedback on giant binoculars either -- some discusson on the Cloudy Nights website.

Giant binoculars are a mixed bag, like everything else in astronomy. Let me start with some negatives:

1. They're heavy and clumsy to move around. Mounting them is a major issue. Think in terms of a permanent mount. Parallelogram mounts can be used but they look huge and require heavy counterweights (Google image searches will turn up an example or two). I've built a one of a kind non-parallelogram mount that involves a counterweight and chair, all on wheels for use only on smooth surfaces like my driveway concrete.
2. In 'giant' size I'm aware of only Fujinon 150's with right angle eyepieces which cost much more than the straight thru version. Straight thru viewing requires special attention as regards body position/mount design. I don't think that its possible to view straight up or close to it for extended times if you're standing.
3. As with smaller sized binocs of higher quality the eyepieces are fixed (no interchangeable eyepieces) which of course means fixed magnification.
4. I haven't found a practical way to use OIII/UHC filters. Nor have I been satisfied with finder scope solutions (this may be a bigger problem with how the Nikons are designed).


The pluses:

1. The views are wonderful. My Nikons provide a 3° FOV which is ample enough to satisfy my sky sweeping style. And the light gathering power of 120mm objectives deliver many DSO's -- globular clusters are quite bright -- the detail visible in M42 is a delight -- open clusters are beautiful. Two eyed viewing with quality glass is great.
2. Though I'm still tweaking the design of my mount I'm able to view all parts of the sky comfortably enough.

So, mixed bag, yes. For me the Nikons are keepers.

Bob Polcyn
Posted 07/04/2008 03:54PM #3
Sorry I am not closer so you could try the Vixen 125mm 25-75x binoscope I own. Beautiful wide field views of the sky in seeming 3-D. They are like two RFT 5" refractors and while there is color on the edge of the moon, seeing it appear round and like another world makes up for it nicely. A friend "made" me buy these several years ago and he was really right, they are one of my favorite ways of seeing the sky.