PhilW
28-01-2010, 09:09 AM
For sale is a Vixen NA120S (neo-achromat) OTA. It is 120mm aperture & 800mm focal length. This is a Petzval design with four elements in two groups. It comes with rings, dovetail plate, 2" diagonal, 1.25" adapter and a Baader fringe killer filter. Condition is excellent.
This scope's great strength is as a deep-sky refractor. It has high contrast, and the Petzval design gives it a wonderfully flat field. With a low-power eyepiece it becomes a kind of super RFT (eg an XW40 produces a true field of 3.5 degrees).
On very bright objects such as the moon and Jupiter, it does display visible CA - for which the fringe killer is useful, and is therefore included. It is not really optimised as a planetary scope.
$850 + shipping or best offer.
This scope's great strength is as a deep-sky refractor. It has high contrast, and the Petzval design gives it a wonderfully flat field. With a low-power eyepiece it becomes a kind of super RFT (eg an XW40 produces a true field of 3.5 degrees).
On very bright objects such as the moon and Jupiter, it does display visible CA - for which the fringe killer is useful, and is therefore included. It is not really optimised as a planetary scope.
$850 + shipping or best offer.