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View Full Version here: : First Hand report new 13mm Televue Ethos


ausastronomer
16-05-2007, 03:25 AM
Hi all,

I got to use the new 13mm Televue Ethos (100 AFOV) under the stars last Sunday Night at TSP, in Larry Mitchell's 36"/F5 Obsession and in Barbara Wilson's 20"/F4 dob on several targets. I also got to use it in a Televue 85 at a "private" gathering yesterday afternoon on selected terrestrial targets and in a Televue NP127 on some test targets. It is absolutely outstanding. I would estimate that right at EOF, image quality is 95% as good as it is on axis. I really am stunned. I can't believe how good the image quality is right across the FOV. Colour reproduction is nice and cool. As cool and neutral as I have ever seen in a Televue eyepiece, where whites appear white not cream. Eye relief for non eyeglass wearers is very good, it is difficult to use with glasses on, but you can fit a dioptrix to it. This eyepiece is a prototype and Al Nagler wasn't letting it out of his sight, so I feel quite privileged, to have been able to spend as much time as I did with it (maybe it was the Aussie accent). Production is still about 6 months off and pricing is not yet determined, nor is the entire focal length range. What I can say is they are going to sell a lot of them, regardless of cost.

I am a Pentax XW fan through and through, but I have to take my hat off to Al Nagler on this occasion. I have to say it is revolutionary and taken widefield eyepieces to a new level. Queue up people :)

CS-John B

slice of heaven
16-05-2007, 05:07 AM
Sounds like the widefield I've been waiting for has finally arrived.
With a review like that from you, I'm one that will probably be standing in line for a couple if the final product is as good.

Thanks for sharing the news. :)

h0ughy
16-05-2007, 07:02 AM
I can see you stopped at customs after a police chase from TSP.......... Thanks for the personal feedback!! Looking forward to the photo opportunity shots with the hunk of glass and the designer

RB
16-05-2007, 08:16 AM
Thanks for the report John, very interesting indeed.
Looks like I might have to fill in the gaps of my EP collection with a few new Ethos models.

:thumbsup:

Starkler
16-05-2007, 08:21 AM
Damn you John. Uncle Al is going to want more for them after your glowing endorsement :doh:
:P

casstony
16-05-2007, 09:27 AM
Hi John, how does the eye relief compare to a type 4 Nagler?

wavelandscott
16-05-2007, 09:47 AM
I was thinking the same thing...first "create" at least a perceived gap and then convince my wife that filling this "gap" is of greatest imperative...at least I have 6 months or so to get my new message across!

John, I am glad that you got a chance to see/use the eyepiece...your comments match everything else I've read...it sounds like a winner for UNcle Al (and Team)!

Rodstar
16-05-2007, 01:10 PM
Sounds like a ripper, John!

Did you find the "spacewalk" feel at all disorienting? Some folk complain when the FOV is very large that it can be TOO large.

Did Al Nagler indicate what the likely range will be, and how long it is likely to take to bring out the full set?

I might just place an order for the whole lot on that recommendation! (subject first to selling the wife and kids on eBay)

Kal
16-05-2007, 01:37 PM
OK, now I am envious!!!! :sadeyes:

StarLane
16-05-2007, 04:27 PM
Was the edge performance consistently good with all test scopes?
Is there any distortion??

Cheers.

wavelandscott
16-05-2007, 06:27 PM
I was thinking the same thing but thought first I would list them in the "trade or swap" section right here on IIS first...

I suspect that once the "Ethos" is avaialble commercially there will be lots of spouses available for trades...:P

circumpolar
16-05-2007, 07:40 PM
Here are some pics from Cloudy Nights http://www.cloudynights.com/item.php?item_id=1654

This also gives a representation of the AFOV of 100deg compared to 82deg like Naglers.

matt
16-05-2007, 07:49 PM
Wow.

They look to be quite lengthy.

ausastronomer
17-05-2007, 04:54 AM
Well to be honest, I feel very privileged.

I was the 5th person in the world to look through it, at a proper astronomical sky target. Many looked through it at NEAF, but this was only on printed test targets which were set up 30 feet away on the wall. Sad thing is, I can't even claim to be the first Aussie to look through it, Andrew Murrell went before me. The 3 people in line before Andrew were Al Nagler, Larry Mitchell who owned the 36"/F5 telescope and Alan Dyer, the author from Sky and Telescope.



Yes it is, it is about 170mm or 180mm tall at a guess. It isn't as heavy as I expected for its size, it weighs about 70% to 80% of the weight of my 17mm Nagler T4.



Yes, the edge performance was outstanding, even in Barbara Wilson's 20"F4 dob without a paracorr. I also compared it in Van Robinsons Televue 85, to an 11mm Televue Plossl. The TV 85 is F7.0 and the Ethos was sharper, with less distortion, at the edge of its 100 deg AFOV than the plossl was at the edge of its 50 degree AFOV.



Minimal, its one of the most distortion free Televue eyepieces I have used.



Not as good. I use both the 12mm and 17mm Nagler T4's with glasses on. I couldn't use this with glasses on and get close to taking in the full field. The eye relief is perfect for non eyeglass wearers and inadequate for use with glasses on.



That effect is caused by the high degree of pincushion distortion in some Televue eyepieces, not the FOV. Some Panoptics are well known to cause this effect. This eyepiece has minimal distortion hence this isn't a problem. You do need to use it for a period before you are capable of taking in the full field of view.



They haven't planned any other focal lengths yet because he wants to leave this in the market for a while and gauge all the user feedback, before designing other focal lengths. This is 6 months off the shelves and the only one that will be initially going to market. Other focal lengths will follow but they may be some time off. Despite claims by many on the internet, they have no clue as to pricing. My guess is, selling your wife and kids will require you to also pitch in the dog and the neighbours to cover the cost and that's casting no aspersions on your wife and kids :)

Keep in mind that I wasn't able to do a direct comparison against other eyepieces under night skies, so I don't know how it is for contrast and light throughput. Also keep in mind I was observing unfamiliar targets. What I saw impressed me no end. Under daylight conditions contrast appeared very good and the images were certainly bright and clear so I can only assume it performs well in these aspects.

CS-John B

Satchmo
17-05-2007, 08:18 AM
John, I'd imagine that concern about star sharpness at the edge of a 100 degree field is not that important as the extra field is only providing an extra feeling of immersion? I know with my 82 degree field EP's I rarely direct my gaze to the edge of the field as theres some discomfort involved.

Mark

skies2clear
18-05-2007, 04:04 PM
" Despite claims by many on the internet, they have no clue as to pricing. My guess is, selling your wife and kids will require you to also pitch in the dog and the neighbours to cover the cost and that's casting no aspersions on your wife and kids "

Thanks for the very informative view John. Your comment above may prove to be the only thorn. Let's hope it is "relatively" affordable, because it sure sounds like a beauty!!!!

CS
Nick