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Ethos and TEC140

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#1 fuerelisa


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Posted 12 April 2021 - 05:31 PM

I have a TEC140 on order (12 months never seemed so long...). Which Ethos EPs/Ethoses/Ethoi would you choose and why? I'll primarily be observing from my club's dark sky site and I'm mostly interested in low power surfing and DSOs. I already have the E13mm. Thanks!

#2 rkelley8493



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Posted 12 April 2021 - 06:00 PM

I use the 21 Ethos a lot in my 130 f/7 Apo. It gives really good low power high contrast views on expansive objects like Andromeda, The Double Cluster, Sagittarius Star Cloud, Orion Nebula Complex, and much more. I can almost take in the full 100ยบ in one glance, but I have to move my eyes just a little to see the edge of field. Speaking of the edge, all stars are in focus & pinpoint regardless of their location in the field of view.

Not an Ethos, but the 31T5 Nagler is a very good complement to the 21 Ethos. They're a good 1-2 punch when it comes to Deep Sky surfing and sweeping the Milky Way.

#3 havasman


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Posted 12 April 2021 - 06:12 PM

You'll want the 21E. And you'll likely also want either the 4.7or 3.7E at some point too because you'll probably want a close look at some results of your sweeping. But the 21, well that's pretty much a given.

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#4 junomike



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Posted 13 April 2021 - 04:33 PM

The 17E is amazing however the 21E has a better separation from your current 13E.

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#5 turtle86


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Posted 13 April 2021 - 04:47 PM

Another vote for the 21E.  It gives wonderful low power views in my 130 AP GT and I'm sure it would do the same for a 140 TEC.


Eventually, you'll want a higher power Ethos as Dick suggests.  

Edited by turtle86, 13 April 2021 - 04:48 PM.

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#6 RAKing



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Posted 13 April 2021 - 04:48 PM

I used most of the Ethos at one time or another in my TEC 140.  For low power, I loved the 21 and for medium power I actually liked the 10mm better on some nights than the 13.  I also used the 8, the 6, and the 4.7 - a lot!  In fact, those are the six eyepieces I carried around for years.  cool.gif  


These high quality optics go together very well.  The only variables are the sky conditions (transparency and seeing).





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#7 paulh83


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Posted 13 April 2021 - 10:01 PM

I have a TEC-140 and a complete set of Ethos. I also have the 41mm Panoptic and 31mm Nagler. Since you already have the 13mm, I would get the 31mm Nagler if the priority is low power surfing. My usage is about equal among the trio of 21E, 31N, and 41P. However, if I had to pick one low power eyepiece to go with the 13E, I would split the difference and go with the 31N. If it must be an Ethos, the 21E is a good step from the 13E.

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