Using the Vixen VMC-260L
I would like to offer a few notes about the Vixen VMC-260L. I don't want to offer a big review, but just a few important points which may not have gotten out there in the past.
I have been involved in astronomy for almost thirty years. For most of that time, I did not have a budget which would allow me to purchase the telescopes I might have really wanted. I mostly used small refractors and Dobsonians. I never complained, as these scopes offered me a great deal of pleasure at a low price.
A few years ago, I decided it was time to upgrade. This decision proved fortuitous, as the deals which were available on telescopes in the late 2000's were just fantastic. To avoid boring you with details, I will just say that my living room is now much more crowded than is Ed Ting's, as shown on his scopereviews web site.
The Vixen VMC260L, which I bought new, is a scope which always gets attention from people whenever they see it. I have found this to be rather amusing, because if anything, it is a scope which has made very little impression on me! I do not make such a comment in a negative way. It just is not a scope I really think about when I am using it, or even when I'm not, and that might actually be a good thing. Overall, I like the scope far better than a C14 which I owned just before I got it.
Perhaps the Christmas-style color scheme has something to do with the attention. The scope is metallic green and white with red graphics. It's really quite attractive. On the other hand, it does not seem like fine equipment the way many Japanese scopes do.
The overall design and construction of the telescope is like something made for the military. Everything looks very beefy, like it is made to last until the big crunch. The finish is good but not at all smooth. The rear casting is massive and should take most anything you can hang on there. I have used a Starlight-1 photometer head on it, and it felt very solid. The large handle on top makes it easy for one person to mount the scope, and it feels light and well-balanced when doing so.
There are a couple of odd items which are the main reason I am writing this note, however. Although the scope is described as a Vixen Modified-Cassegrain telescope, it appears to be something along the lines of a Klevtsov telescope, which has lenses in the secondary mirror holder, which the light passes through twice - going up, and coming back down. The strangest thing about this scope is the coatings which were used on the lenses in the secondary holder. They have a strongly peach-colored cast, and they do color bright things in the sky peachy! The Moon is, in particular, a big cratered peach in this telescope.
Also, in comparing the telescope to a ten-inch reflector, it was apparent that the Newtonian showed dimmer stars. The Vixen has images that are really quite dim for its size. I seemed to be losing about a magnitude. It is like using a scope that is, effectively, a bit smaller than its aperture. I do not think this is just because of the obstruction, but also, once again, the coatings. Besides being orange, they are also quite reflective. The coatings are just inexplicable, and I can only speculate that they have to do with the Klevtsov design. I can't understand why else such coatings would be used on a $4000 scope when the cheapest Chinese scopes now have dark green coatings.
Another unfortunate feature of the design is that the focal reducer does not come to focus visually. This limits the scope to higher powers, as it does have a focal length of 3000mm. This restricts its use and makes me feel that it would not be good as an only scope.
On the good side, the optics are as sharp as can be, and contrast is really excellent for an obstructed scope. Jupiter is particularly good in the scope, and I have often wondered if the peach coatings were helping things on the big planet. Saturn looks nice but the colors are not as pure as in a Newtonian, likely due to the coatings - but it is really, really sharp. Even the Moon can take unbelievable powers along the terminator, despite the aforementioned color issues. And, cool-down is not much of an issue with the scope. I get good steady views in half an hour or so, on most nights. That is a big change from the old C14, which seemed to never cool down.
Deep sky objects look great in the very flat and distortion-free field, so long as such objects are small enough to fit in the field.
Another oddity is that the focusing knob sticks out quite far in the back and may hit on large equipment. The knob can be removed for a little more clearance, but there is still a threaded rod underneath which will stick out somewhat. This was an issue on an old-fashioned photometer I was using. On the other hand, focusing is very smooth and though it is not a true two-speed focuser, the design of the knob with two diameters on it makes it seem like one. In most positions the scope has no image shift when focusing, but there have been times when it was moving ten arc-seconds or more.
For some reason, the designers made the 2" ring with the setscrews on it so short that it can be hard to get the fingers in there to tighten the setscrews. I've had to resort to needle-nose pliers!
The collimation of the scope is very difficult, but it seems to hold up well once done. I added Bob's knobs and these were a great help, though they do hit on the dust cap. I have been told that I have the second version of the secondary holder, which is supposed to be superior. I must note that a large puffy logo sticker which was on the center of the secondary holder fell off and landed on the primary mirror when the scope was almost new. This was NOT a good occurrence and they should glue the sticker on there better!
My overall opinion of this telescope is that it is very nicely made, with very sharp optics, but it is also something of an oddity. The coatings are just inexplicable. A few design considerations are just weird.
I hope that my opinion does not sound too lukewarm, however. I have used this scope for hundreds of hours since 2008 and it has always made me happy. I like to observe planets and it is wonderful for the task. The very best views of Jupiter and Mars which I've ever enjoyed were with this scope. In fact, I believe it has not been recognized as one of the very best planetary scopes out there.
I have used many scopes, from small APOs to big reflectors, and this telescope is really, really awesome for the planets. I suspect the scope was intended more for imagers, but it is very capable for visual use at higher powers, as one would expect from a scope which is basically most like a Maksutov. I would recommend the scope to anyone who understands that it is unusual and limited in certain ways.
I would also recommend to Vixen that with a few design changes, they could have an incredible world-beater of a telescope on their hands. It is a mystery to me why this scope is so near to being great and yet is not upgraded into a new model which would be, truly, great. - Glen Ward
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