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Mike B
Starstruck
Reged: 04/06/05
Posts: 4443
Loc: shake, rattle, & roll, CA
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Hi John-
Glad yer enjoying the new glass!  What you've described is about what i'd imagined, and i found the bright & neutral tone of the 30mmP i tried to be quite beautiful. The ER was decent, too... i'd say their 16mm number is about right. I could comfortably view the entire FoV while wearing glasses.
Quote:
I can't imagine it would be very good in a fast Newt.
But this conjecture i can say from experience is, unfortunately, quite true! A Paracorr *might* clean things up a bit (i didn't have one at the time  ), but the Dob's FC combined with the astig you're seeing would really work against it. Without a Paracorr in my F4.55 Dob, it was pretty much a mess in the outer 40% FoV. 
I was saddened with the results i found with the Dob/Paragon mix... i really wanted it to be a winner. It wasn't. But it sounds like with your scope, and for your purposes, it *IS*! Congrats!
mike b
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Just for giggles- Next time when the money comes out the ATM, scream "I Won!, I Won!"
* * 15" F4.55 Starsplitter Dob * *
 Pacheco State Park
 Fremont Peak
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HAC
professor emeritus
Reged: 04/07/05
Posts: 534
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Thanks everyone for your supportive words.
I will say this for the TMB, I think it was designed for medium to slow refractors, like TMB would make; whereas, the TV eyepieces were really instigated by the emergence of large fast dobs, although I know TV tests their eyepieces in the "MPT" (or something like that) which is essentially a f4 refractor I believe. The key here is fast optics.
So I believe some of the difference that is being seen is by design.
Lesson for today: Don't pound in a nail with a screwdriver.
Thanks again guys, I really appreciate the feedback so at least I know I'm am providing some value.
Take care,
john
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Bring Back The AP Waiting List Thread and Let Freedom Ring
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Tom Trusock
Reged: 02/26/02
Posts: 27299
Loc: Alternate Reality (TM)
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Quote:
Hey Tom,
I did view the moon and noticed no dust. The eyepiece was fresh out of the box however and was immaculate.
I'll keep an eye out and let you know if this changes.
Thanks John. I'm hoping that with the 30 this won't be much of an issue. It's really not with the 40 - you don't use a 40mm eyepiece as a lunar eyepiece.
T
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There are two theories to arguing with my wife. Neither one works.
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Tom Trusock
Reged: 02/26/02
Posts: 27299
Loc: Alternate Reality (TM)
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Quote:
Many TV eyepieces show a hint of astigmatism near the edge when I go naked-eye vs with glasses.
We've been this path before hoof. By the design, there simply isn't astigmatism in those particular eyepieces you're talking about. I don't know where it's coming from, but you need to seek another solution for that particular case.
You didn't believe me before, so I doubt you'll believe me now, but I'll restate it anyway.
But hey don't take my word for it - Call Al and ask him.
T
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There are two theories to arguing with my wife. Neither one works.
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Tom Trusock
Reged: 02/26/02
Posts: 27299
Loc: Alternate Reality (TM)
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Quote:
So I believe some of the difference that is being seen is by design.
My thoughts as well.
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There are two theories to arguing with my wife. Neither one works.
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hoof
Pooh-Bah
Reged: 04/07/05
Posts: 1421
Loc: Irvine, CA
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Actually, Tom, that's not a bad idea. I might call Al and ask him about the effects of myopia on the effective focal plane of the eyepiece, and if that could alter the correction characteristics.
Incidentally, proof that mypoia (or far-sightedness) alters the focal plane placement is simple: Have a nearsighted person focus the eyepiece. Now adjust it for a 20/20 person. Notice the eyepiece is shifted. Remember that the focus point of the telescope is fixed, thus you're changing the focal plane's position in the eyepiece. If that doesn't alter the characteristics of the eyepiece in some way (maybe minor), I'd be surprised. What I don't know is how that focal plane shift would alter things for TV eyepieces, other than what I've seen and observed. But the focal plane *does* shift with myopia, unless you choose not to adjust focus to get sharp images in your view.
Other eyepieces have not had this issue. My Meade eyepieces can be focused to sharp pinpoints near the edge with and without glasses, and that includes the 30mm, 18mm, 8.8mm, 6.7mm and 4.7mm UWA's, along with the 14mm Series 4000 UWA. The odds that some eye defect would affect only TeleVue eyepieces is very unlikely.
Either way, Mr. Nagler might know what's going on, so I might give him a call. I assume I just call the TV number on their website?
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Jonathan Hoof
15" F/4.14 Discovery Truss
8" F/5.9 Orion XT8i
6" F/6 Intes-Micro MN66
4.5" F/4 Orion Starblast
80mm F/7.5 Orion 80ED
18x50 IS Canon binoculars
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Tom Trusock
Reged: 02/26/02
Posts: 27299
Loc: Alternate Reality (TM)
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Well you could stand on a street corner and yell at the top of your lungs, but I don't think that would get you very far.  The number on the website would probably be a better choice.
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There are two theories to arguing with my wife. Neither one works.
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Mike B
Starstruck
Reged: 04/06/05
Posts: 4443
Loc: shake, rattle, & roll, CA
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Quote:
...but I don't think that would get you very far.
Hmmmm... that 'splains a lot. Might be less hassle, too... you wouldn't believe the looks i get from passing motorists! And that from merely a "local" call...
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Just for giggles- Next time when the money comes out the ATM, scream "I Won!, I Won!"
* * 15" F4.55 Starsplitter Dob * *
Pacheco State Park
Fremont Peak
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hoof
Pooh-Bah
Reged: 04/07/05
Posts: 1421
Loc: Irvine, CA
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 Funny idea Tom Maybe I'll give the yelling at the top of my lungs a try ...
The odd thing I find here is the lack of consideration to observation and logic (if focal plane doesn't move relative to 'scope but eyepiece does, then focal plane relative to eyepiece has changed). This reminds me of people trying to convince others of the world being round. No matter what logic or indirect observation was made, many people wouldn't believe the world was not flat. It took people of Sage status to finally convince people of that fact. Thus I'll call our Sage, Mr. Nagler on Monday, and find out. Maybe if he confirms that the world is round ... er ... that the focal plane in the eyepiece shifts with myopia (and what the resulting effect upon his eyepieces is), you'll actually consider what I say on the issue.
Don't misunderstand me, I very much respect you and what you do for our community, I'm just puzzled that you both reject my observations, the possibility that myopia can cause different effects upon eyepieces, and the logic I presented to support my claim that the focal plane changes. But it's obvious that my arguments fall on deaf ears, so I'll stop posting until I get word from someone you *will* listen to.
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Jonathan Hoof
15" F/4.14 Discovery Truss
8" F/5.9 Orion XT8i
6" F/6 Intes-Micro MN66
4.5" F/4 Orion Starblast
80mm F/7.5 Orion 80ED
18x50 IS Canon binoculars
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Tom Trusock
Reged: 02/26/02
Posts: 27299
Loc: Alternate Reality (TM)
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Quote:
Funny idea Tom Maybe I'll give the yelling at the top of my lungs a try ...
The odd thing I find here is the lack of consideration to observation and logic (if focal plane doesn't move relative to 'scope but eyepiece does, then focal plane relative to eyepiece has changed). This reminds me of people trying to convince others of the world being round. No matter what logic or indirect observation was made, many people wouldn't believe the world was not flat. It took people of Sage status to finally convince people of that fact. Thus I'll call our Sage, Mr. Nagler on Monday, and find out. Maybe if he confirms that the world is round ... er ... that the focal plane in the eyepiece shifts with myopia (and what the resulting effect upon his eyepieces is), you'll actually consider what I say on the issue.
Don't misunderstand me, I very much respect you and what you do for our community, I'm just puzzled that you both reject my observations, the possibility that myopia can cause different effects upon eyepieces, and the logic I presented to support my claim that the focal plane changes. But it's obvious that my arguments fall on deaf ears, so I'll stop posting until I get word from someone you *will* listen to.
Hoof,
We've just been there and done that, and I'm tired of the round robin. It didn't seem to matter what I said before and it probably won't now either, but I'll make one final attempt.
Yes, you're right. The focal plane WILL shift, and yes aberrations will be revealed (which ones and how severe is open to debate) but that's not really what I'm objecting to.
The issue I have is how you make your claim that the naglers show noticeable astigmatism.
Frankly, I just think it's misleading to post that these eyepieces have astigmatism when no one else has seen it (every other account I've ever heard has been attributed to the users own vision), and by design - they don't. Posting "I see astigmatism, quite probably due to the interaction of my uncorrected vision, with this eyepiece on this scope, viewing this target" is one thing - and perfectly acceptable. Posting "Naglers have astigmatism" is another entirely.
The way you say it, it sounds like everyone should see astigmatism in them, when even your truth (if you like, I'll even state that I can concede the possibility although I think other things are equally likely) is that you apparently have run into a very special, rather distinct set of events that give you a net result which differs from that which 99+% of other users will ever experience.
So, I guess I don't know that I have as much of an issue with your post as how I see it presented.
T
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There are two theories to arguing with my wife. Neither one works.
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csa/montana
Astro Ambassador
Reged: 05/14/05
Posts: 28272
Loc: montana
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Quote:
But it's obvious that my arguments fall on deaf ears, so I'll stop posting until I get word from someone you *will* listen to.
It would be most appreciated, when you post again on "TV" subject, please start a new thread, so this one can get back on the original subject, the 30mm Paragon.
Thank you!
Carol
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Carol
AstroTech 16" Dob (Thanks ASTRONOMICS!)
AstroTech 66ED / Vixen 80MF/AstroTech Voyager
Masuyama's 7.5, 15, 25W, 35mm,
Tak LE 5mm B/TMB 3.2
7mm Pentax XL, 10mm Pentax XW
14mm Meade 4000 UWA
22mm Pan, 35mm Pan
DreamCatcher Dobservatory, #2
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NorthCoast
Carpal Tunnel
Reged: 12/05/04
Posts: 2195
Loc: Westerville, Ohio, U.S.A.
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Anyone compare the 30mm Paragon to the WO 28mm UWAN? I know they are different animals, but, I am curious.... I have the 28mm UWAN and the 40mm Paragon. I am very happy with both, however, the 28mm is a beast for grab-n-go! I had to upgrade to a 90mm refractor from a 66mm just so people when using low power would know what end to look into...  Anyway, I am considering getting the 30mm based on the 40mm experiernce but only if it would be a good choice for replacement for the 28mm UWAN.
Thoughts appreciated.
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Mark
Hold the "Alt Key" and type 248 on the number pad for °
Edited by NorthCoast (05/16/08 08:52 PM)
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Daud
sage
Reged: 08/05/06
Posts: 250
Loc: AZ, Scottsdale
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Quote:
I'm curious to hear what you think of it John. I suspect that for the money you'll be pretty happy with it.
T
..and even more so for the current $100 price.
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WO ZS110 | Meade SN-6 | Johnsonian 16" goto | Celestron Regal 8x42 | Canon 15x50IS
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