Explore Scientific 20mm 100 vs Nagler T5 20mm
Posted 17 March 2013 - 10:35 PM
I was expecting the 20mm Nagler to deliver more satisfying views, darker sky, slightly more contrast on DSO's etc but my first couple of sessions with these two have not been so conclusive.
My impression so far is that the ES 20 / 100 matches the Nagler T5 20mm in terms of contrast and light throughput on DSO's and shows stars pretty sharply across the whole field of view with my fastest scope, an F/5.3 12" dobsonian.
The additional eye relief, wide field and more immersive view of the ES 20 / 100 are winning me over, rather to my surprise.
Am I missing something here ?
Perhaps my scopes are not fast enough to allow the Nagler to show it's edge ?
I'm wondering if anyone else has compared these two and what are your views on their relative performance if you would care to share them ?
Posted 18 March 2013 - 01:42 AM
Posted 18 March 2013 - 01:51 AM
Posted 18 March 2013 - 10:14 AM
Up until that point I was a 17T4 advocate. The 14 ES 100° not only met the 17T4 in transmission, but offered a higher magnification at the same FOV and lacked that finicky T4 eyeplacement!
It wasn't long before my 20T2 was ousted by the 20 ES 100°. Again, the ES showed It could run with the TV and offered noticeably better transmission.
I will say that the 20T2 does have a "legendary" feel to It and It's one of a few eyepieces that can be used in a fast Dob (F4.5) without a Paracorr and have near perfect edges.
Posted 18 March 2013 - 10:43 AM
Posted 18 March 2013 - 12:16 PM
Good seeing night in a 10" DOB 4.7 and a 111 APO F7.7
I found they were more similar than different
20T2 had better color saturation
20T2 had better ablitly to show the whole FOV at once
20T2 had a bit more pop/sharp to the image
20 ES 100 more immersive
20 ES hair better transmission
20 ES larger FOV
20 ES lighter
Bottom line for me was there is no need to swap and get the 20 ES if i have the 20T2 and also the other way around.
The 20ES is a great EP!
Posted 18 March 2013 - 12:48 PM
I am surprised at this outcome. I really like ES eyepieces, just for some background info. But, I think the nagler 20 is one of the best eyepieces I have used. That is a huge endorsement for the 20mm ES100 to me.
Sean, Just to be clear, Tony (Tank) and I are referring to the older 20T2. The newer 20T5 is rumored to have better (newer) coatings and transmission which changes the game for me as that was a big part of my decision.
Also, I don't use Dobs so the edge correction wasn't as critical for me. If I did though, I probably would have kept the 20T2 like Tony (Tank) did.