Vixen VMC200L

[toryglen-boy]

Howdy

My Astro has the VMC200L on sale for $1200, has anyone used one? was it any good? thoughts? good for imaging? stack up well to a GSO RC ?

thanks

:)

[AlexN]

IMHO - A better imaging scope than a GSO 8" RC... The VMC200L has a much flatter field of view, comes standard with a better focuser, has a dedicated focal reducer available, and will provide a flat field across a 35mm sensor. The same can not be said of the RC... Expect to add at least $400 to the price of the RC for a focuser..

I noticed the VMC200L for sale at Myastroshop and at AOE.. $1200 is CHEAP for these scopes. They are usually more like $1900...

If you've got your heart set on the GSO RC, Andrews has one of the first series GSO RC's for sale at $999... Bargain in any sense of the word...

[Hagar]

Hi Duncan, I had a VC200l and sold it to buy an 8" RC. I am still yet to be convinced it was the right move to make.
Imaging with the VC200L was effortless, the field was flat right to the edges of the field with the only thing I didn't like was the thick spider vanes which gave bright stars a very large diffraction spikes and tended to make the bigger stars appear as diamond shaped. The focuser was not the greatest but did work OK. No replacement focuser was available but I think that has changed. Vixen also make a dedicated reducer for this scope which reduces the focal length to 1200mm.

The 8" RC suffers from a dodgy focuser which must be replaced and works quite well once you get a suitable field flattener and position it correctly.

All up both scopes have their faults and with some expense they can be overcome. Same choice again and I probably would have stuck with the VC200L and arranged a machine shop to reduce the thickness of the spider. Both are a bit touchy on collimation and require good collimation for good results.

I hope this helps.
Some images taken with a stock standard VC200L and some with the reducer can be viewed on my website.
http://www.darkskyau.com/cm/thumbnails.php?album=10

[Paul Haese]

Only criticism I have of the Vixen is the square stars caused by the thick vanes on the secondary.

I would not buy a first series RC. The ones we bought were the second series. The first had trouble with the optics and were all sent back. So I am thinking it was one from the second series that is for sale Alex?? Even in that case you need to fix the baffle and change the focusor too. As well as dove tail plates.

Each scope has its strengths and weaknesses. Choice is yours. I am pro RC but many others have the Vixen.

[toryglen-boy]

thanks guys for your input

so, whats the difference with the VC and the VMC ?

its only the VMC on sale

:)

[AlexN]

VC200L is a VISAC optical system. ( VIxen Six-order Aspherical Cassegrain )
VMC is a Vixen Maksutov Cassegrain.

Simply, the VC200L has a corrector setup inside the primary baffle tube to correct the field, where as the VMC200L has a corrector lens just behind the secondary mirror... It is a modified Mak Cass, rather than having a corrector plate that covers the entire open aperture of the OTA, the secondary is held in place by a spider, and the corrector covers the entire aperture of the secondary mirror, greatly reducing dew problems commonly associated with the Mak Cass type scopes.

Both give stunning images, although its been said on many forums that the VMC is more suited to visual astronomy than the VC, both are at home in an astrophotography setup

[casstony]

In an open tube design the dielectric mirrors are attractive in terms of reducing future maintenance.

[leinad]

My understanding was due to the corrector being located behind the sec. mirror on the VMC, this doesn't provide a flat field image, best suited for photography.
The VC however has a flat field across as 35mm sensor due to the corrector located in the focuser tube.
Not sure where you found that reference Alex.

VMC is also F/9.75, VC is F/9



The Vixen VC200L indeed has some improvements needed. But so can be said for other scopes as well. *cough* RC 8".

My Vixen has milled spider vanes and Feathertouch focuser with customized backplate made by Starlight instruments to mount the focuser to the tube. Sooo much better. Others I believe use PDF's.



VMC is more of a Mak. design; VC closer to a CDK design.
VMC suited for visual, VC for photography.

Save your money and look at either a Mewlon 210, VC200L, or RC 8" All have their merits, produce great images, and will need aftermarket cosmetics.

[AlexN]

There would be no point in having a corrector if the scope did have a resultant flat field. What I've read is that the VC is better for imaging than the VMC, and the VMC is better for visual than the VC, but both scopes can do both tasks well. Just what I've read...

Daniel is right - F/9.75 vs F/9.

Paul - I don't know all the specific batches and what was wrong with each, all I know is the andrews site lists it as "Guan Sheng RC8" (Ritchey-Chretien) 8" f/9 superceeded OTA" I was only aware of two versions, the one you and I bought, and the current version..