Post by Chicago Astronomer - Astro Joe on Dec 4, 2011 19:33:35 GMT -6
Binoviewers
I have enjoyed my limited time with the binoviewers that some Chicago Astronomers have used during some of our sessions. Certainly, using both eyes while viewing most celestial objects brings a sense of a 3-D experience...especially when used on the Moon. Saturn is also great in binoviewers and the Galilean satellites "pop" out.
Sometimes they work, sometimes they don't. Some telescopes don't offer enough "inward" focus to bring the image into sharpness or the need to use an adapter - usually a barlow tube - to bring it into focus.
The higher end Binoviewers, (Televue, Denkmeier, Baader, Siebert..etc...) are just too expensive for this astronomer.
But, it's time for me to get my own.
I came across a deal on Celestron Binoviewers...
Description
The Stereo Binocular Viewer allows you to adapt two eyepieces to your telescope and view with both eyes simultaneously. In addition to eliminating eye fatigue associated with viewing through one eye for a prolonged period of time, this 1.25-inch bino viewer also provides a three-dimensional effect when you're observing many celestial objects. In addition, it will improve contrast on deep-sky objects and solar system objects. The Stereo Binocular Viewer is designed to work with Schmidt-Cassegrain telescopes (SCT) and many refracting telescopes.
The Stereo Binocular Viewer requires you use two eyepieces of equal focal lengths and optical design. Your telescope will come with one or more eyepieces - you will need to purchase a matching eyepiece for use with the binoviewer.
High quality FMC BAK-4 prisms to reduce light loss Quality control inspected for collimation and performance.
Fully Multi-Coated BAK-4 prisms
Foam lined aluminum storage case
Eyepiece diopter scales for sharp focus
With some promos and rewards...I could get it down to about $169.00
Researching...I came across the Orion Binoviews...
Description
The Orion Binocular Viewer comes with a thread-on 2x Barlow lens, so you can choose two levels of magnification. The hinged aluminum housing contains fully multi-coated BAK-4 prisms that provide high light transmission. You can use almost any matching pair of 1.25" eyepieces. Individual helical focusing collars ensure a sharp focus for each eye.
The viewer's 1.25" nosepiece is threaded to accept filters. The Binocular Viewer works with all types of telescopes. On reflectors or short-focal-length refractors you may need to use the barlow lens to accommodate the requirement for 4" of additional inward focus travel.
Features -
Includes thread-on 2x Barlow lens so you can choose two levels of magnification
Hinged aluminum housing contains fully multi-coated BAK-4 prisms for high light transmission
Reflectors and short-focal length refractors may require the short 2x barlow lens
Includes storage case and caps for eyepiece holders and barrel
Both offer free shipping and are comparable - but I like the Orion better. It comes with 2x barlow lens tube adapter and it also has three nylon screws on each eyepiece insert. Binoviewers need to keep both eyepieces in pretty much the same vertical orientation with each other. Single set-screws "tilt" the eyepiece in the barrel...causing a double image at times - but the three set screws will enable centering nicely.
Reading the extensive reviews on both these binoviewers, they seem to be accepted as decent optics and providing satisfactory images.
With already on hand several 25mm plossls, I'm set with starter eyepieces. And with the 1.25" to 2" adapter...I'll be able to use the Binoviewer on the C11 with little problem. And maybe...I can even use it as a make-shift viewer when imaging - using one ocular for the camera and the other to track and confirm.
Now, just to order the Orion Binoviewer.
But wait...
I came across this..
Same Orion binoviewer package...but at 30 bucks cheaper...!
Still with free shipping, I'm under $140.00 on an accessory that I hope will enhance my observation experience. I may use the pair for limited public observation session, but as a rule - as with all the various eye-spacings and diopters with our visitors...not very practical. But for our solid regular fans and supporters, I will be happy to share to special views.
Ordered and done.