Paddy has recently upgraded to the 17 Ethos and I think he sold his 17 Nagler and 28 WO UWAN to fund it. I am not sure if his Nag was a T4 or not, but when I lent him my 17 Ethos at Snake Valley back in March he had ordered one himself in a few days. Said in his 16" scope it was no contest.
The closest direct comparison I have done was a 13mm T6 Nag against a 13mm Ethos and again the Ethos won hands down. Stars were noticeable sharper, easier to get precise focus, better eyerelief and as for that big field!!
I sold nearly all my Nagler eyepieces for the Ethos. The Ethos are fantastic in my 16" and my 8" SCT. I have the Ethos 8mm to 21mm and didn't bother with the shorter focal lengths. The Ethos are certainly better than the Nagler, but not always.
I have been very happy with them, however, after purchasing my WO FLT110 APO, I didn't think that the lower power (13, 17 & 21) Ethos were that great with this scope, and was disappointed, but only a little. It was ok with the 8 & 10 Ethos though. However, I soon rectified this with the purchase of the Delos, as these eyepieces were much better suited to the WO FLT110 APO, however, to date I have only used the higher power Delos (4.5 & 6mm). I currently have a 10mm Delos on order.
The 17mm Nagler would perform well in the refractor compared with the Ethos, however, in the 16" and the 8" SCT, the Ethos wins easily.
So, it is not entirely fair to compare these eyepieces, as it will depend on the scope it is used with, as I discovered.
Hey Peter, that's not an eyepiece case you want to leave on the train! I can really appreciate a well thought out case. How sad am I
Question; Why the hell would I want to take it on a train?
Anyway, if you think that is bad, you should see the rest; I have cases for everything. Actually, the guy that does my cases is really good and thought out the best way to do it. Once I have all the Delos, I will get another made; now that is sad
Thanks for the feedback gents. It's much appreciated.
Looks like a 17mm and 21mm Ethos might be on the horizon.
Hope they work well in the new Baader 2inch Cool Ceramic herschel wedge I have just ordered :-)
You won't be disappointed with the either the 17mm Nagler or 17mm Ethos, as they are both very fine eyepieces, and either would be awesome with your Tak Mewlon. It will just come down to what you can afford really.
One consideration is whether or not you use specs when observing. I had a chance to compare the Nikon 17mm, the Ethos 17mm and a type4 nagler 17mm. The other observers present found the ethos and nikon slightly sharper and with better contrast than the nagler - but I found the opposite as only the nagler had enough eye relief for me to wear my specs.
There wasn't a lot in it, really, they're all exquisite eyepieces.
In my very subjective opinion... Ethos is a generation or two ahead in terms of design, engineering and performance. It's not just a FOV thing. It's an all-round higher performance EP, except for eye relief. If you want to observe with eyeglasses on, forget the Ethos. I'm not knocking the T4s though. They are a superb classic design.