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Re: Baader Hyperions

Started by wpaolini, 07/17/2008 03:18PM
Posted 07/17/2008 03:18PM | Edited 07/17/2008 03:20PM Opening Post
Since the Hyperions are a 68 deg afov EP, they compare best with either the Panoptic line or the Pentax XW line.

* The Panoptic line gives up available focal lengths to the Hyperions and XWs as there are no short focal length offerings.

* The Pentax XW line gives up nothing IMO to the Hyperions and is a clear notch above both optically and in availability of focal lengths.

* Both Pentax XW and Panotics give up the ability to change the focal length of the eyepiece which the Hyperions accomplish through their fine tuning ring concept.

* Both PentaxXW and Panotics give up the modular concepts which the Hyperions are built around in attaching cameras, etc (see the Hyperion system chart).

* The Panoptics give up rectilinear distortion control to the Hyperions and XWs which both control it much better.

* The Hyperions give up fov darkness uniformity to both the Pentax XWs and Panoptics as you can see a general lightening in the fov about 20% from the field stop.

* The Hyperions give up off-axis sharpness and lateral color control to both the Pentax XW and Panotics which substantially do not have these issues.

* The Pentax XWs and Panotics give up bang-for-buck when compared to the Hyperions as the Hyperions cost much less.

* The Hyperions give up build quality in compared to the Panoptics or Pentax XWs. They are still good but not at the premium level we see in the other two lines.

* The Hyperions and Panoptics give up interior "dust control" to the Pentax XWs which are sealed eyepieces so theoretically over time air/dust particles will not work their way in.

I find the Hyperions all work excellently in my 102 f/8 APO and I enjoy them very much in that instrument. On-axis sharpness and transmission are on-par with any other wide field IMO. Coloration I would put somewhere between the Panoptic and the XW, with the Panoptic being the warmest. I would characterize them as "very good" eyepieces. The "great" characterization I would say is more appropriate to the XWs and Naglers and Ethos for wide fields IMO. Panoptics, for me, don't quite make the "great" category, but only because there is too much rectilinear distortion for my tastes.
Posted 07/17/2008 04:26PM #1
* The Hyperions give up fov darkness uniformity to both the Pentax XWs and Panoptics as you can see a general lightening in the fov about 20% from the field stop.

* The Hyperions give up off-axis sharpness and lateral color control to both the Pentax XW and Panotics which substantially do not have these issues.


To add a bit to Bill's excellent contribution:

- It is my understanding that Hyperions and the Stratus's are essentially the same eyepieces. In using a Stratus or two, mostly the 13mm in a variety of scopes ranging from F/4 to F/13, I found both these aberrations to be distracting. And unlike some simple widefield eyepieces, the off-axis sharpness was an issue even in slower scopes.

- On the plus side, these eyepieces do have an appropriate amount of eye relief and a nice big eye lens, both of which help provide a nice comfortable view.

- On the plus side, on axis they are bright and sharp...

But for me, the bright edge and the "considerably less than perfect edge correction" meant that these were not keepers but rather a stopping place on the way to better corrected eyepieces.

YMMV.

Jon