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Stellarvue 80/9D Refractor
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I have used many of the Chinese made refractors sold by Orion finding the 90mm with the 910mm focal length the most useful for my seeing conditions and ease of use requirement.
One missing capability of the 90mm was it could not use 2 inch eyepieces and I wanted to try out a higher quality objective. Since Apochromatic type scopes were beyond what I could spend on this hobby I purchased the Stellarvue 80/9D for $399. I bought the 2002 version. The 2003 version is $449 and the key difference is that the 2003 version has the retracting dew shield where mine does not. At the time of this writing Stellarvue is still selling the 2002 version. No eyepieces or diagonal comes with this OTA.
The Stellarvue 80/9D is an 80mm (3.1 inch) achromatic scope with a 750mm focal length for a f/9.4 focal ratio. I have it mounted on an Orion AZ-3 altazimuth mount. I’ve done a review on this mount here on Cloudy Nights and you can find it under the review for mounts section.
The scope does come with a red dot finder but I prefer a right angle, correct view, 50mm viewfinder. The right angle provides more comfort when searching for objects and the 50mm allows me to find many of the Messier objects that are my favorites and are within the capability of this scope like M42, the Orion Nebula. Note: I had to file down, significantly, the Orion 50mm finder base to get it to fit into the Stellarvue’s dove tail mount. So, if you do not own a 50mm finder and decide to buy one for this scope you may want to buy Stellarvue’s instead of one from Orion.
The dew shield on the Stellarvue is longer than most. In one evening my finder fogged but my objective remained fog free through the night. With other scopes I’ve owned if my finder fogged so did my objective.
Colorful double stars have become a passion for me in the last few months. I like them because when the Deep Sky Objects (DSOs) are washed out by the haze or a light layer of clouds, which happens often here in North Carolina during the Summer, I can often still view my growing list of favorite double stars. Also, for small scope users this is about the only chance to see color and nice color contrast.
I found on the Chinese made 90mm refractor scope that pushing it to 60 times its objective diameter in power (212X) degrades the image except on the Moon. On double stars that are close together, say 2.5 seconds apart, this kind of power will introduce a diffraction ring around the primary that hides the secondary.
I have pushed the Stellarvue to 202X (65 times the diameter) on Izar (in Bootes) and there is a slight and very thin diffraction ring around part of the primary but the secondary outshines the diffraction ring and is clearly seen. I’ve used about 180X power on the Double Double in Lyra with no diffraction rings noticed. Also, on Rasalgethi, in Hercules at 150X and no diffraction rings were noticed.
The Stellarvue’s other advantage is the ability to use 2 inch eyepieces. With a 40mm, 2 inch Plossl, with 62 degree field of view I get about 3 degrees field of view through the Stellarvue to sweep the Milky Way; very nice. If the 90mm could use 2 inch eyepieces with its 910mm focal length it would get about 2.5 degrees field of view.
Accessories that I am using with the Stellarvue which I am happy with are:(prices are as of 30 August 2003 and do not include shipping and handling; just for reference)