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My 102mm Vixen achromatic refractor

If I haven't already said so, let me reiterate that I am a novice at amateur astronomy, so keep that in mind as you read the material below.

In September 1998 I bought a VX102 achromat from Orion. I would have liked to buy the ED or fluorite version, but couldn't really justify the expense at my present level of expertise. Mainly I just wanted a decent scope that would fit in my car more easily than the 8" dob, and wouldn't require collimation after a trip. In that respect I've been completely satisfied.

You can get the specs from Orion's web site, so I won't bother with them here, except to say that the scope has an aperture of 102mm (4 inches) and a focal ratio of 9.8. (so the focal length is 1000mm)

Bright objects such as Jupiter have a distinct blue fringe around them, but it's not objectionable in my opinion. I've also noticed a very faint blue fringe around Saturn, but I had to look for it before I ever noticed it.

I've been mostly looking at planets, bright Messiers, and double stars. I've been sticking with about 150x or so with the planets; the air just hasn't been still enough here lately to allow higher powers. Mostly I use my Televue 32mm and 26mm plossl eyepieces, along with a 2x or 3x barlow. I stuck in a Meade 6.7mm plossl even though I don't really care for the small hole and the short eye relief (I wear glasses) and was pleased to see a nice little Airy disk and a couple of diffraction rings around the brighter stars. The out-of-focus rings looked ok to my unexpert eye, but I need to take a book out with me to do a somewhat more rigorous star test.

I think the highest power I've used so far was about 225x: the 20mm eyepiece that came with it, and a Televue 3x Barlow in front of the diagonal, making it effectively about a 4.5 barlow. I couldn't really see much more that way, so I backed down to a lower power. I don't think it was the telescope's fault, just that the seeing was not up to it. On one clear night I used 200x on Saturn and had a perfectly clear, steady image, but usually 150x is about the limit the seeing will permit, at least in town lately.

Most of my observing is done in the northern Kentucky suburbs of Cincinnati, so the heat from all the buildings and the light pollution doesn't help. Still, I had no problem finding the Ring nebula, although I had to use averted vision to see the central 'hole'. I have yet to take this scope to the country, so maybe I might be able to see the ring more clearly if I did.

Concerning the mount, well, I can't really say much. The only other scope on an equatorial mount that I've used is a Meade model 285, which is a 60mm f/15 refractor on a cheap mount. Compared to that mount, the Great Polaris is rock-solid. But I suppose there really is no comparison between the GP and a dirt-cheap mount. It's not nearly as good as the mounts on the Clark telescopes in the Cincinnati observatory. :-) But anyway, I like it. When you unlock it, you can push the telescope around with just your finger and thumb, although you have to make sure it's balanced. Adding a heavier eyepiece can unbalance it. It does vibrate when you focus, but I suppose it's hard to avoid that. Dampens down in a second or two.

I didn't buy a motor with the mount, because it's just one more thing to set up, and I don't really need it. I have no immediate plans to get into astrophotography; I want to learn the sky better before I try anything like that. It would certainly make it easier to keep a planet centered at high powers, but it's not that much trouble to reach up and twist a knob. Then again, I haven't been making sketches of what I see. If I did that, I might appreciate a motorized mount more. I know that many authors recommend this, but so far I've been content to ogle the sky.

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