The TeleVue is a high quality, relatively fast, short focal length,
apochromatic refractor with an unobstructed wide field designed for use
with a camera. The vast majority of catadioptric scopes are f/10 or
slower and designed primarily for visual use. They are designed to
minimize the size of the central, secondary mirror obstruction and
consequently will only fully light a field of about 10-15mm diameter
before possibly serious vignetting starts. Most provide enough back
focus to mount a camera but the camera was a secondary consideration in
the design, not the primary one.
Larger sizes of Meade and Celestron catadioptric scopes are of what's
called the Schmidt-Cassegrain design. A Schmidt-Cassegrain that was
specifically designed for photography would put the TeleVue to shame
with respect to field of view and lack of coma and chromatic abberation.
You can find them in observatories and a few custom built scopes but I
don't believe any are made that you and I could likely buy.
Chuck Norcutt
Winsor Crosby wrote:
> The images look terrible to me, more like something from one of those
> ads in the back of a magazine except the price should be $39. I don't
> understand why, but astronomical telescopes seem to make lousy camera
> lenses. Televue telescopes are about as good as they come for small
> astronomical telescopes but here are a bunch of terrestrial shots
> that would cause a camera owner to change brands.
>
> http://www.televue.com/engine/page.asp?ID=297
>
> I would rather spend the $1000 on a good sharp zoom, or a telescope
> better than this one.
>
> http://meade.telescopes.com/site_search/index.php?
> brand=51&cat=17&b=Meade&c=Telescopes
>
> Actually you could probably buy both for that price.
>
>
>
> Winsor
> Long Beach, California, USA
>
>
>
>
> On Oct 9, 2006, at 7:27 PM, USHER99@xxxxxxx wrote:
>
>
>>This mirror telescope was recently written about as being super
>>light (18 oz
>>or 1.5 Kg) and will collapse into a package less than 6" long. It
>>should be
>>mountable on OM via C to OM. I wasn't that impressed with the
>>sharpness of
>>the images, though have never used anything like this. They are
>>made in
>>Hungary and are backordered for 2 months.
>>Mike
>>
>>_http://www.tothtelescope.com/?
>>p=details_models&id=9&PHPSESSID=59b9d0604b8de6e
>>3a3234d1e1167902c_
>>(http://www.tothtelescope.com/?
>>p=details_models&id=9&PHPSESSID=59b9d0604b8de6e3a3234d1e1167902c)
>>
>>
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