2013-05-14T21:00:00
Rated 2 out of 5
Not really worth it.
Even though it's quite cheap, you're better off just cropping and zooming in post.
Keith C.
2013-01-15T19:00:00
Rated 4 out of 5
Works as advertised
I have used this with a Rokinon 800mm f/8 catadioptric (mirror) lens on a Nikon D200 and had no difficulty focusing the lens. With the Rokinon, at least, it works well. Other mirror lenses may be different.
Due to the long focal length of the above combination (1600 mm, and effectively 2400 mm on the DX format D200) very high shutter speeds are necessary to avoid blurred images due to camera shake. 1/2,000 of a second or faster is recommended. Given an effective aperture of f/16, you'll need a very bright day or a very high ASA - or both - to realise acceptable images. Even locking the camera down on a sturdy tripod doesn't work; at these magnifications, there's enough residual camera body movement from the mirror to induce camera shake.
In my experience, many people confuse poor lens performance with camera shake. Long telephotos are very difficult to use correctly, and require a fair bit of practise. They're not easy. But I was satisfied with the image quality of the tele-converter, and feel that it offers good value.
Charlie
2012-12-12T19:00:00
Rated 4 out of 5
Inexpensive reach
Best use is extending reach of old T-mount teles for new DSLRs.
SHAWN B.
2011-03-05T19:00:00
Rated 4 out of 5
very good product!
I use the 2X teleconverter with 2 different telescopes.
Capitan
2010-06-05T21:00:00
Rated 4 out of 5
Excellent on SC Telescopes
This is essentially a Barlow lens (multiplier, or Tele-converter) in a T-mount package. In my experience I found it did NOT work at all on my 800mm Catadioptric lens. It does work VERY WELL with my Schmidt Cassegrain Telescope. The difference being the amount of focal adjustment possible in a SCT vs, a standard camera sized photographic lens.
This is a recommended accessory for astrophotography, but NOT for t-mount catadioptric lenses.
JEFFERY S.
2010-05-22T21:00:00
Rated 4 out of 5
excellent tele converter
the teleconverter is great. I ve used at the university s telescope ( meade 16"). Great results.
Paola G.
