The Type 4 Naglers - REVIEW

Posted by Mark Gemmell   12/09/2022 01:18PM

The Type 4 Naglers - REVIEW

Type 4 Naglers - My Experience

This review is based on using all three of them in a 10" F/4.7 Dob. I first owned the 12mm Type 4 Nagler. The second one I owned was the 17mm, and finally I bought the 22mm. All were bought used but in like new condition. I first used the 12mm Type 4 Nagler in 2012. I grew to like it over time and had gotten used to it. I think I bought two more of them over time, after selling the first one. The more I used it, the more I disliked it. Isn't it supposed to be the other way around? --Scratches head--, lol.

12mm Nagler Type 4

So, I will start off reviewing the 12mm Nagler Type 4. It definitely has a steep learning curve. The eye relief is long, but the funny thing about the 12mm T4 is that once you get to the right spot and seeing the field stop, eye placement becomes very critical. You can fix this by setting up the instajust. This is the top part, (black with green lettering and green lines for those of you who are not familiar with these). You pull it upwards to where you need to have it set at just the right level so that blackouts will not occur. If I remember correctly, there are 4 "click stop" settings. I believe two settings upwards was just right. However, I do NOT like any type of contact with my eye socket and eyepieces, and I like to "hover" above the lenses, so this adjustment was a no-go for me. It is good for many who use this eyepiece, and what it is intended for to set it just right.

I found that I could not "hover" over this eyepiece and feel comfortable, like I do when I use my Baader Morpheus eyepieces, or Vixen LVW's. It just isn't happening with the 12mm Nagler Type 4. After owning my third one, I felt that this just wasn't something I could use and like, so I eventually sold it. What I did notice about this eyepiece however, was the really high light transmission it offers. When using it, the light transmission was really high, which is a bonus for Deep Sky Observing. When looking down into the lens, the glass looked like it was barely even there. It is very well made, which is quite common for TeleVue eyepieces and they are well known for this. The field stop is razor sharp looking into this eyepiece and well defined. It also barlowed well when you set the instajust just right. I also tried it on planets and it fared well in that regard.  No "ghosting" or internal reflections. TeleVue baffles the insides of their eyepieces really well. The edges in this eyepiece are somewhat "soft" without a coma corrector, which is to be expected in a short focal length telescope, however, I found that I could use it without one, and it was acceptable.

17mm Nagler Type 4

This eyepiece is very well made just like the 12mm, but I was not a fan of this eyepiece at all, so it didn't last very long and I sold it too. This was my first experience with field curvature when using the Type 4 Naglers. It was very strong and distracting. I did not have a coma corrector at the time, so I cannot comment on how the coma corrector would have eliminated the field curvature I was seeing. Younger eyes can accommodate the field curvature....older eyes have trouble focusing and is worse, so the 17mm T4 would be excellent for younger eyes or older eyes if you own a TeleVue Paracorr, or other type of coma correcotor. Eye positioning on the 17mm was nowhere as critical as the 12mm T4 was however. it was easy to position my eye over the lens for a comfortable view. I did not own it long enough to comment on any other aspects of the eyepiece, but from what I saw, it was nice except for the field curvature my old eyes were experiencing.

22mm Nagler Type 4

I owned this one for much longer than the 17mm T4. Some field curvature was present, but at the time I owned a 2 inch GSO coma corrector and it eliminated some of the field curvature I was seeing with this eyepiece, but over time it got to me and I also sold this as well. (I detest seeing field curvature in any eyepiece). Some of the FC still remained even with the GSO coma corrector, and it eventually was too bothersome. The 22mm is a very comfortable eyepiece to use though. In fact, it IS the most comfortable out of all of the Type 4 Naglers. Eye placement is nowhere near as critical as the 12mm and even more easy to use than the 17mm Type 4 Nagler. It works excellent with filters, barlows really well and is a really nice Deep Sky eyepiece, except for the FC I saw in it. I've used other eyepieces in this range that do not show ANY field curvature and which I like better. Some of the ones I liked better were the 20mm Nagler Type 2, 22mm Vixen LVW, 21mm Baader Hyperion, (with 14mm fine tuning ring), 22mm Astromania, 22mm Ultima LX, 20mm APM 100°, and the awesome 22mm TeleVue Panoptic . None of the ones I just mentioned needed a coma corrector, except for the 22mm TeleVue Panoptic and the 20mm APM 100°. A coma corrector would likely make the others perfect, but I am willing to not use one because I just don't want another piece of glass to deal with any longer any more.


I would have to say that the Type 4 Naglers are all very well made, (TeleVue really cares about how they make their eyepieces, and it shows a lot), but they are just not for me. I prefer the Baader Morpheus for their easy eye placement, etc. In order from worst to best, (again, I wouldn't say ANY of them are bad), here is my list:

12mm Type 4

17mm Type 4

22mm Type 4

Again, thanks for reading and I would like to thank Astromart for letting me write up this review. Astromart is an excellent source of information and a great place to buy and sell.

Clear Dark Skies to All !!!