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Michael Scherman

Lagoon and Triffid Celestron C6 Hyperstar4

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High power eyepiece question

Started by japacheze, 01/18/2003 04:20PM
Posted 01/18/2003 04:20PM Opening Post
Recommendations, please. I'd like to find a 1.25" 5-6mm with afov 50ยบ+ and eyerelief of 10mm+ , that does not rely on a built-in set of barlow lenses to achieve its short focal length and maintain descent eyerelief. Also, price must be below $150. Would consider eyerelief as low as 7mm if necessary. Anyone know of such an eyepiece? Thanks
Posted 01/18/2003 06:25PM #1
OZ,
I recommend an Orthoscopic, which seems to meet your wish list! You can buy new (University Optics), or you can try used, I have found many great Ortho's on astromart for around 40$. Chris Brown

There's something on the Moon! 8O
Posted 01/18/2003 09:23PM #2
Requirements:
1. focal length 5mm to 6mm
2. 1.25" barrel
3. >= 50 degree apparent field.
4. eye relief 10mm or more w/o a built-in Barlow.

If there's a product like that, I don't know of it. Why the prohibition of a built-in Barlow?

The 3-6mm Nagler Zoom comes close with 10mm of eye relief and a 50 degree apparent field. It probably does have a negative field group, but it has just 5-elements total so maybe you will cut it some slack on that score. It does, I note, fit the 5-6mm focal length range literally. :-) The 5mm Tak LE is also a good choice. I think it has 9mm of eye relief and 5-elements (not sure), but it does have that negative field group, too.
--
Mike