Edge-on eyepieces
Has anyone tried the Orion "Edge-On" flat-field eyepieces? For either imaging or visual use? http://www.telescope.com/control/product/~category_id=eyepieces/~pcategory=a... User feedback appreciated.
I bought the 16mm flat field eyepiece for my 6" Celestron Schmidt-Cass and it seems to work great. The field of view is decent but it's not expansive. I confess my observations with it have thus far (in my three weeks with it) been limited to Mars and the Moon. Because the Moon is the only edge-to-edge object I've seen through the eyepiece I'm limited in my observing experience. It looks great. Happy New Year, Seth -----Original Message----- From: utah-astronomy-bounces@mailman.xmission.com on behalf of Chuck Hards Sent: Sat 12/29/2007 10:17 PM To: Utah Astronomy Subject: [Utah-astronomy] Edge-on eyepieces Has anyone tried the Orion "Edge-On" flat-field eyepieces? For either imaging or visual use? http://www.telescope.com/control/product/~category_id=eyepieces/~pcategory=a ccessories/~product_id=E0084 User feedback appreciated. _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com
That's along the lines of what I'm looking for. Wide-field is a marketing buzzword, an aesthetic quality, and of secondary concern to a practical observer; if it's around 60-degrees (especially on eyepieces under about 20mm focal length), I'm happy. Sharpness (resolution) is always the most important quality of an eyepiece. It's also somewhat of an esoteric characteristic, unfortunately, judging from what I've looked through at some start parties in recent years. The real test would be to use it on some terrestrial targets. Look at a straight, vertical object in the distance- the edge of a tall building, or a smokestack, for example. It should fill the field top-to-bottom, or nearly so. Move the telescope so the object is near the edge of the field and see if it "bends" slightly either inward or outward. Field curvature has to be fairly severe to notice it on a celestial object. Coma is easy to detect, a curved field isn't so apparent. Thanks, Seth! On Dec 31, 2007 3:33 PM, Seth Jarvis <SJarvis@slco.org> wrote:
I bought the 16mm flat field eyepiece for my 6" Celestron Schmidt-Cass and it seems to work great. The field of view is decent but it's not expansive. I confess my observations with it have thus far (in my three weeks with it) been limited to Mars and the Moon. Because the Moon is the only edge-to-edge object I've seen through the eyepiece I'm limited in my observing experience. It looks great.
participants (2)
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Chuck Hards -
Seth Jarvis