I had the opportunity to try out the new TV 13mm Ethos eyepiece that has a 100-degree apparent field of view at a star party. The eyepiece was being used in a TV NP127is f/5.2 apo refractor, and I observed some deep-sky objects with it. I did not get the opportunity to try out the eyepiece during the day, so here are my initial impressions of using it under the night sky.

TV 13mm Ethos Eyepiece

Although I have been using TV Naglers that have an 82-degree apparent field of since the mid-1980's I was surprised how much larger the apparent field of view (FOV) appeared in the 13mm Ethos. It was noticeably wider than those I have had in my Nagler 12mm Type 4.

The eye relief is reportedly 15mm and I found it comfortable, although I found it took some time to get use to was positioning my eye to see the entire FOV. I tried to get my eye as close as possible without getting my eyelashes on the eye lens. I was never able to completely see the entire FOV without moving my eye or head around to see it. However I have heard from others that they were able to learn to position their eye so to be able to see the entire FOV.

In terms of the view through the eyepiece I did not note any loss of contrast in the 13mm Ethos, as the detail in M8 the Lagoon Nebula and M20 the Trifid nebula appeared sharp and contrasty. In addition stars appeared sharp to near the edge of the FOV. The same held true for other deep-sky objects that I observed with this eyepiece.

It is my understanding that there will be other eyepieces in the Ethos line. Recently a price $620.00 was announced for the 13mm Ethos eyepiece. Even with this price these new eyepieces may be the next hot seller for TV.

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Article © 2008, Eric Jamison, All rights reserved.

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