Late to the Ethos party...

[omahaastro]

So I haven't changed my front line eyepieces for almost a decade now... I love them, consisting of nothing but a 7/9mm Nagler, several type 4's and the 31T5.

I love the 12mm and 17mm type 4's... but can I justify financing the cost of a 13mm Ethos by selling them both, and not miss them?

Is the 13 Ethos versitle enough to replace both of these eyepieces?

Is there any loss of transmission/contrast to gain that 100 degree field?

[Marko]

You are not alone on this party. I too have just picked up the 13mm Ethos on AstroMart and used it only once but in very poor skies so cannot comment on it much but from what I recall others on this board saying I thought the contrast actually gets better than the Nagler type 6 so I don't believe anything is lost except space in your eyepiece case (they are HUGE). Also picked up 6 and 8mm Delos again, never used yet on a real dark sky.

I too would be interested in this thread. There is another thread started by Faith that has quite a few comments by the way.

[nicoscy]

Comparison.jpg

Some numbers to you relevant to your Obsessions. My feeling is that it CAN replace both eyepieces, but then again I drank the Ethos Cool aid very early on. Contrast/sharpness should be better on the Ethos but even if you do not notice a difference, the wider TFOV does make the experience more "immersive". I once looked through a 6mm Ortho. Then through a 6mm Ethos. I keep the Ortho as a reminder of why my Ethos were such a good purchase... The views were remarkably similar (high quality Ortho with less glass contributed), but I hate soda straw kind of views...

[Don Pensack]

So I haven't changed my front line eyepieces for almost a decade now... I love them, consisting of nothing but a 7/9mm Nagler, several type 4's and the 31T5.

I love the 12mm and 17mm type 4's... but can I justify financing the cost of a 13mm Ethos by selling them both, and not miss them?

Is the 13 Ethos versitle enough to replace both of these eyepieces?

Is there any loss of transmission/contrast to gain that 100 degree field?

Well, the 13 Ethos has the same field of view as the 17 Nagler, but higher magnification, and the same power as the 12 Nagler, but larger field.
It'll be usable on all your scopes. The advantages of an Ethos, other than field correction, superior color rendition, and simply awesome field of view is that you can actually get by with fewer eyepieces because the true fields are so large you don't need to drop the power to have a "finder" eyepiece. In my scope, the 13 yields 140X at a 3/4 degree field size. I can do some serious observing at that power, yet the field is large enough to be used as a finder eyepiece.
So how many eyepieces do you need? Well, you simply pick them by field of view. A reasonable set would have a 1 degree, 3/4 degree, and 1/2 degree field. And then you'd add to that by figuring out if you really needed a super high power or a super low power. I found, for instance, there is still ample reason to have a 31 Nagler, regardless of the field size of the 21 Ethos.
That's a serious group of telescopes, and I think you would find the 13 Ethos usable in all of them.
Just remember that coma becomes MORE visible the wider the apparent field of view. If you don't have a Paracorr yet, you will.