128 replies to this topic

[Cathexis]

Greetings & Happy New Year to All,

 

I've been waiting for a nice 20mm to fill the gap betw'n my 35mm Pan & 10mm Pentax XW. The three

best candidates (based on on-line reviews & comments) seemed to be either of the TV Naglers or the

Pentax XW. 19mm & 22mm Pans were also on the radar screen but the Naglers & XW seemed to get

the best reviews. It was basically a matter of seeing which would show first as used, pristine, & a good

price. I took the plunge on a "new-opened" Nagler Type 2 20mm with a nice (for me) price the other day.

 

The purpose of this post to twofold:

1. Does anyone have the specs on the Type 2 they'd post? Like what TV posts online for current EPs ?

    (I can only find the field stop number on their site for the Type 2).

 

2. How do the two compare ? All older reviews praise the dickens out of the Type 2 as a classic EP.

    Newer ones give same praise to the Type 5. Have I lost anything by settling for a Type 2 20mm?

 

Please accept my thanks in advance,

 

Cathexis

 

FWIW, My current "best" EP's are: 35mm Pan, 10mm XW, 8mm Delos. Also, 2" Everbrite & BIG

Barlow with Panoptic Adapter and 2"-1 1/4" compression ring adapter. OTA is C-6R.

Edited by Cathexis, 29 December 2014 - 01:14 PM.

[howard929]

Some of the time it's always best to include telescope information when asking about eyepieces...

[star drop]

It is an excellent eyepiece, I had one from when they were first introduced (1986?) up until a few years ago when I switched to 100° apparent field of view eyepieces. One night a while back a friend and I were looking at M51 for an extended period of time. He was contemplating grinding a 20" mirror and was curious about how a galaxy would look in such a telescope. We started with a 35mm Panoptic eyepiece and then in succession the Naglers 20mm (type 2), 17mm (type 4), 13mm (original) and 9mm (original). Using them in a 25" f/5 without a Paracorr there was no complaint other than the seeing was not up to par for the 9mm. The 20mm also performed very well in a 13.1" f/4.5.

[davidmcgo]

Which scope is an important question, and with Paracorr or not.  In an f4.5 Newtonian without a Paracorr, the 20mm and 14mm XWs have a LOT of field curvature.

 

Dave   

[bgi]

I recently researched the answers to the question you're asking.  I found a trove of information by doing a custom search in titles only for "nagler 20mm" in the eyepieces forum.

 

I have no direct experience with either.  The summary of what I found:

 

T2 is a beast - very heavy - often causing balance problems.  Several people commented that the T2 presents colors better than the competition, and the views are very comfortable.  The earliest model has no filter threads.  TeleVue added the safety cut-out on the latest revision.  Folks say the T2 corrects for or counters coma, so a paracorr isn't needed in a Newtonian.  This is fortunate for the weight reduction.

 

T5 has tight eye relief that bothers some.  It is much lighter, easier to handle, and has slightly better transmission.  Best used with a Paracorr in a Newtonian.

 

My T2 should be here this week.  Maybe the clouds will go away soon.

 

FWIW: I replaced my 35mm Pan with the ES 30mm 82.  I've been very happy with the change.  The Pan's distortion made me seasick.  The wider view, more useful exit pupil, and darker background are an improvement.

 

Some weight comparisons.

 

T2 20mm        1055g

ES 30mm 82  1018g

ES 20mm 100  954g

T5 31mm          894g

Pan 35mm        650g

 

You should be pleased with your choice!

Edited by bgi, 29 December 2014 - 02:03 PM.

[Cathexis]

Good replies, thanks!

 

To those who suggested scope details were important perhaps I assumed too much with the phrase,

"OTA is a C-6R." Specifically, my scope is a Celestron model C-6R 150mm f8 achromat refractor with

a focal length of 1200mm. I have swapped out the stock focuser for a Orion Crayford 2-stage I like alot.

It rides on a CG-5 ASGT mount. My usage is for observing, not imaging.

 

As usual, **another** series of cloudy nites around here should afford me no end of opportunities to crawl

through older threads about, "Nagler 20mm". Though I would prefer my eyes be gazing upwards rather

than at my PC screen I remain grateful for all the info I always find on this site.

 

Cathexis

[Eddgie]

In general, the older Naglers had more pincushion distortion, less eye relief, and older coating technology.

 

All of the Naglers have all had excellent off axis performance.  That is just a product of the design, where  in essence, a built in barlow is used to slow the light cone entering the field stop to a level were even an Erfle type eyepeice would give excellent off axis performance.

 

As for the pincushion, matters to some, won't matter to others, and even teh T5 still has some pincushion.  I personally do not find a problem with pincushion for night time use, but many people do.  

 

As for eye relief, the differences typically are not great with the exception of the T4s, which really do have much better eye relief than the other designs.

 

As for coatings, at very high power, I think the older T2s are indeed an oh so very bit dimmer than modern designs but this is (to me) difficult to see unless you are working at very small exit pupils, where the slightly dimmer image of the older T2s seemed to make me have to hold back magnifcation a bit more than with the T6s.

 

Excellent eyepeices, but unless you get it really cheap, I would just go for a T5.  State of the art, and probably as good as Naglers will ever get.

Edited by Eddgie, 29 December 2014 - 03:17 PM.

[BarrySimon615]

Here is a size comparison of both the older 20 mm T2 and current 20 mm T5.  I got my Type 5 to replace the Type 2.  Size consideration mostly.  Performance seemed to be about equal to me, although I do not recall any specific details.

 

Barry Simon

Attached Thumbnails

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[Paul G]

Owned them both, compared them pretty extensively. Objectively I couldn't see any difference in the views, subjectively the t2 has MUCH more of the floating out in space feel. Not sure why it would feel so different other than the large eye lens. I kept the t5 due to size but must admit the 20 t2 is the only eyepiece I've regretted selling.

[Scanning4Comets]

20mm T5 will have better transmission, (newer coatings, etc). I would get the 20mm T5 if I were you...but....

 

And here's the but.....

 

There are other options with excellent transmission, (20mm ES 68, 20mm XW), and don't weigh a ton like the 20mm T2.

 

To me the 20mm T2 has seen it's better days and is old in comparison to newer offerings. It DOES have excellent correction, but I can get the same correction using a 22mm Vixen LVW at a fraction of the weight!

Edited by Scanning4Comets, 29 December 2014 - 06:44 PM.

[Cathexis]

At a rough kilo in weight I guess I should be glad I got free shipping.

Can't wait to heft and use this Beastie ! Nice replies from everybody.

 

Cathexis

[Procyon]

Holy...that's not a hand grenade...that's a bazooka rocket launcher shell. Does it even fit in a case lol... The views must be great though.

[Tank]

20T2 is a great EP im sure you will love it

vs the newer Wide field EPs 82/100 AFOV you don't loose much if anything at all

and its better than pretty much everything out there in a fast scope

Haven't really seen a better 20mm WF eyepiece out there

Enjoy

[Scanning4Comets]

20T2 is a great EP im sure you will love it

vs the newer Wide field EPs 82/100 AFOV you don't loose much if anything at all

and its better than pretty much everything out there in a fast scope

Haven't really seen a better 20mm WF eyepiece out there

Enjoy

 

I beg to differ here. The 22mm Vixen LVW has just as good correction and would have better transmission, (less glass), and the weight factor is a HUGE difference between the two. I prefer the 22mm LVW over the 20mm Type 2 any day of the week, plus I can use 1.25" filters on the 22mm LVW and save HUGE $$$.

 

How come you're selling yours bro?

Edited by Scanning4Comets, 30 December 2014 - 11:19 AM.

[Tank]

ANSWERS:

I beg to differ here OK. The 22mm Vixen LVW has just as good correction and would have better transmission (less glass)I don't think it has as good correction but I agree with the transmission slightly better, however were dealing with two different classes here a 65degree vs 82degree!!!, and the weight factor is a HUGE difference between the two YES but for the most part I really don't care about the weight and size of a EP!!. I prefer the 22mm LVW over the 20mm Type 2 any day of the week Opposite for me , plus I can used 1.25" filters on the 22mm LVW and save HUGE $$$ Understand but I have 2" filters and have other 2" EPs which I need and can use the 2" filter for my 1.25" and even my .965" EPs.

 

If the 20mm T2 is so good, why is yours for sale? Reason, I find my 14 ES 100 close enough FOV that I don't need the 20T2 anymore when I had the 14 Delos it made sense to have the 20T2 however now with the 14 ES 100 the 20T2 just offers up a tad more FOV! (I picked ES 14 100 over the Delos 14 due to FOV and with this FL I would be viewing more DSO hence picked the 14 ES 100)  The difference is minimal ES 14 100 vs 20T2 and would not require anything between my 14 ES 100 and my 35 Pan!

 

The 20mm T2 is still Excellently Corrected , one of the easiest EPs to look thru if you don't need 20mm ER for glasses

and still one of the best 20mm out there in the WF category. IMHO

 

These are just my opinions  

[Scanning4Comets]

ANSWERS:

I beg to differ here OK. The 22mm Vixen LVW has just as good correction and would have better transmission (less glass)I don't think it has as good correction but I agree with the transmission slightly better, however were dealing with two different classes here a 65degree vs 82degree!!!, and the weight factor is a HUGE difference between the two YES but for the most part I really don't care about the weight and size of a EP!!. I prefer the 22mm LVW over the 20mm Type 2 any day of the week Opposite for me , plus I can used 1.25" filters on the 22mm LVW and save HUGE $$$ Understand but I have 2" filters and have other 2" EPs which I need and can use the 2" filter for my 1.25" and even my .965" EPs.

 

If the 20mm T2 is so good, why is yours for sale? Reason, I find my 14 ES 100 close enough FOV that I don't need the 20T2 anymore when I had the 14 Delos it made sense to have the 20T2 however now with the 14 ES 100 the 20T2 just offers up a tad more FOV! (I picked ES 14 100 over the Delos 14 due to FOV and with this FL I would be viewing more DSO hence picked the 14 ES 100)  The difference is minimal ES 14 100 vs 20T2 and would not require anything between my 14 ES 100 and my 35 Pan!

 

The 20mm T2 is still Excellently Corrected , one of the easiest EPs to look thru if you don't need 20mm ER for glasses

and still one of the best 20mm out there in the WF category. IMHO

 

These are just my opinions  

 

I've looked through both......22mm Vixen LVW correction is the same, there was no difference when I had both. As for weight, YOU don't care, but others do! 1Lb Vs 2.5 Lbs is a huge difference to a lot of people. As for filters, I'm sure most would rather spend a lot less for the exact same performance, (1.25" filter vs 2" filter), and have a smaller FOV and save HUGE bucks.

 

20mm T2 is a really good EP, I agree, but just way too heavy for man, including myself.

 

PS: There is a  quote option, it does save a lot of wasted time.

 

Cheerz!

Edited by Scanning4Comets, 30 December 2014 - 01:15 PM.

[SteveG]

 

 

 

I've looked through both......22mm Vixen LVW correction is the same, there was no difference when I had both. As for weight, YOU don't care, but others do! 1Lb Vs 2.5 Lbs is a huge difference to a lot of people. As for filters, I'm sure most would rather spend a lot less for the exact same performance, (1.25" filter vs 2" filter), and have a smaller FOV and save HUGE bucks.

 

 

Yes - the weight differences have been addressed.

 

How do you know that "most" would rather spend less for the smaller 65 deg field?

 

While both eyepieces are well corrected, I wouldn't say that the 65 deg eyepiece is providing "the exact same performance" as the 82 deg eyepiece. YMMV

Edited by SteveG, 30 December 2014 - 01:42 PM.

[Scanning4Comets]

 

 

 

 

I've looked through both......22mm Vixen LVW correction is the same, there was no difference when I had both. As for weight, YOU don't care, but others do! 1Lb Vs 2.5 Lbs is a huge difference to a lot of people. As for filters, I'm sure most would rather spend a lot less for the exact same performance, (1.25" filter vs 2" filter), and have a smaller FOV and save HUGE bucks.

 

 

Yes - the weight differences have been addressed.

 

How do you know that "most" would rather spend less for the smaller 65 deg field?

 

While both eyepieces are well corrected, I wouldn't say that the 65 deg eyepiece is providing "the exact same performance" as the 82 deg eyepiece. YMMV

 

 

Ummmmm..because people in general want to save money, unless they are rich and don't care.

 

Yes, both are well corrected......My main concern was the weight.

 

Not much of a huge diff in field...in my scope, the 22mm LVW is 1.2 degrees the 20mm Nag is 1.36 degrees....IMO, the field difference isn't much, hence the lighter 22mm LVW is preferred more IMO.

[youngamateur42]

Im a sucker for oldies and goodies like the vintage naglers. Either type I'm sure you'd be happy

[Paul G]

 

 

 

 

I've looked through both......22mm Vixen LVW correction is the same, there was no difference when I had both. As for weight, YOU don't care, but others do! 1Lb Vs 2.5 Lbs is a huge difference to a lot of people. As for filters, I'm sure most would rather spend a lot less for the exact same performance, (1.25" filter vs 2" filter), and have a smaller FOV and save HUGE bucks.

 

 

Yes - the weight differences have been addressed.

 

How do you know that "most" would rather spend less for the smaller 65 deg field?

 

While both eyepieces are well corrected, I wouldn't say that the 65 deg eyepiece is providing "the exact same performance" as the 82 deg eyepiece. YMMV

 

+1. I find the difference between a 65 deg fov and an 82 deg fov significant.

 

As far as filter size, given the op's question both the 20 t2 and t5 are 2" eyepieces so no difference there.

[Procyon]

 

 

 

20mm T2 is a really good EP, I agree, but just way too heavy for man.

 

 

 

LOL. Is this what you really meant Markus?

Edited by NorthWolf, 30 December 2014 - 04:10 PM.

[Starman1]

Greetings & Happy New Year to All,

 

I've been waiting for a nice 20mm to fill the gap betw'n my 35mm Pan & 10mm Pentax XW. The three

best candidates (based on on-line reviews & comments) seemed to be either of the TV Naglers or the

Pentax XW. 19mm & 22mm Pans were also on the radar screen but the Naglers & XW seemed to get

the best reviews. It was basically a matter of seeing which would show first as used, pristine, & a good

price. I took the plunge on a "new-opened" Nagler Type 2 20mm with a nice (for me) price the other day.

 

The purpose of this post to twofold:

1. Does anyone have the specs on the Type 2 they'd post? Like what TV posts online for current EPs ?

    (I can only find the field stop number on their site for the Type 2).

 

2. How do the two compare ? All older reviews praise the dickens out of the Type 2 as a classic EP.

    Newer ones give same praise to the Type 5. Have I lost anything by settling for a Type 2 20mm?

 

Please accept my thanks in advance,

 

Cathexis

 

FWIW, My current "best" EP's are: 35mm Pan, 10mm XW, 8mm Delos. Also, 2" Everbrite & BIG

Barlow with Panoptic Adapter and 2"-1 1/4" compression ring adapter. OTA is C-6R.

T5 has newer coatings, fewer elements, a lot less weight.

If I had a choice, it's be the T5, but the T2 20mm is not a bad eyepiece by any means.

[Scanning4Comets]

 

 

 

 

20mm T2 is a really good EP, I agree, but just way too heavy for man.

 

 

 

LOL. Is this what you really meant Markus?

 

 

Why would I want a 20mm T2?????

 

Had one.....didn't care for the weight.

[Scanning4Comets]

 

 

 

 

 

I've looked through both......22mm Vixen LVW correction is the same, there was no difference when I had both. As for weight, YOU don't care, but others do! 1Lb Vs 2.5 Lbs is a huge difference to a lot of people. As for filters, I'm sure most would rather spend a lot less for the exact same performance, (1.25" filter vs 2" filter), and have a smaller FOV and save HUGE bucks.

 

 

Yes - the weight differences have been addressed.

 

How do you know that "most" would rather spend less for the smaller 65 deg field?

 

While both eyepieces are well corrected, I wouldn't say that the 65 deg eyepiece is providing "the exact same performance" as the 82 deg eyepiece. YMMV

 

+1. I find the difference between a 65 deg fov and an 82 deg fov significant.

 

As far as filter size, given the op's question both the 20 t2 and t5 are 2" eyepieces so no difference there.

 

 

I was referring to TFOV....not apparent.

 

If you are referring to AFOV, then yes, it is significant...for some.

 

YMMV.....

[Jon Isaacs]

 Folks say the T2 corrects for or counters coma, so a paracorr isn't needed in a Newtonian.  This is fortunate for the weight reduction.

 

I own a 20 mm T2.  I see coma if I view without a Paracorr in a F/4-F/5.5 Newtonian. If it corrected for coma, then coma would be seen in coma free scopes.. I don't see it there..

 

I think it's a top notch eyepiece.. Maybe not quite as perfect as the T-5 but still an excellent performer, well corrected and free of Edge of Field Brightening.. 

 

Comparing it to a 65 degree eyepiece, it's difficult to judge when one of the two is missing 17 degrees..

 

Jon