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Tandum
20-08-2010, 12:26 AM
Does anyone use a 2x powermate with a camera to extend the focal lenght of thier scope?

I want more focal length without paying for another scope and thought a 2X might do it. It would push the 10" newt to 1.9meters @ F7.6 which is useable.

I'm wondering if they introduce any problems when imaging?

Alternately, will a TAK 1.6 extender work in a newt? I could use that in the refractors as well.

riklaunim
20-08-2010, 12:50 AM
You can also use good/high quality barlow like GSO 2.5x APO or achromatic mixed 1.5/2x GSO. There are also good 2" 2x GSO and SkyWatcher APO Barlows.

Tandum
20-08-2010, 01:03 AM
You got any images taken through one of those lenses?

gbeal
20-08-2010, 07:23 AM
Robin,
I bought a while back an Antares 1.6x for this express purpose, but never tried it in the end, just got too hard, and I sold it.
Maybe even try the likes of a decent 1.4x or 1.6x convertor for the Canon or Nikon lenses?
Gary

Garyh
20-08-2010, 07:28 AM
Hi Robin, Have a look at Sieberts barlows.
The 1.5x 2" gets good reviews ex with newts, actually acts like a coma corrector and barlow in one..
I have wanted one for ages! maybe Santa ;)

http://www.siebertoptics.com/SiebertOptics-barlows.html
cheers Gary

Tandum
21-08-2010, 12:20 PM
Cheers guys, those Sieberts are pretty reasonable for a 4 element device and 1.5x would do it. I'm guessing they are not silver inside. Looks like something else to go on the endless list of things to try :)

DavidTrap
21-08-2010, 12:48 PM
Try Mark Lewis - I know he has a 2x Televue Powermate 2inch and has had reasonable success with that on an ED80. I'm hoping to try it one day in my FS-102...

DT