13mm Nagler Type 6 Shootout
Submitted: Wednesday, 19th October 2005 by Mike Salway
Everyone knows the Televue Nagler brand when it comes to quality eyepieces. They have a reputation amongst some amateur astronomers as being the best, with a wide field of view, sharp pinpoint stars across the entire field and high contrast. The Nagler Type 6 range are consistent across all focal lengths. They're also one of the most expensive eyepieces you can buy. So what do you get for your money? Is it worth spending that much money on a single eyepiece?
This article sets out to review and compare the 13mm Nagler Type 6 with 3 other premium eyepieces at the same focal length - the Pentax 14mm XW, the Meade Series 4000 14mm UWA and the newer Meade Series 5000 14mm UWA.
Hopefully this review and shootout will provide you with the information you need to determine if your hard earned dollar is best spent on this premium eyepiece.
Many thanks to Bintel for loaning the 13mm Nagler Type 6 and the Meade Series 5000 14mm UWA for the purpose of the review. John Bambury (ausastronomer) supplied the Pentax 14mm XW from his collection, and the Meade Series 4000 14mm UWA was from my collection.
All of these eyepieces were tested in my 10" f/5 GSO Dobsonian, FL 1250mm, giving a magnification of approx 96x for the 13mm and 89x for the 14mm. The scope was collimated prior to the review.
The review was conducted by myself (an avid observer since July 2004) and John Bambury (a casual observer for 30 years) over the course of 6 weeks under the dark skies of a new moon.
All 4 eyepieces are of similar hybrid widefield design. In fact it is rumoured that the Meade s4000 UWA design is a direct copy of the Nagler Type 1 design. The Pentax has a 70deg AFOV, while the other 3 are wider at 82-84 deg. In real terms, it's a 0.1 deg difference in TFOV, or 6 arcminutes. Not a huge difference, but it is noticeable if you look for it. John did not notice the difference in TFOV as I did, and it's true to say that opinions are divided amongst the amateur astronomy community as to whether the TFOV difference is really that noticeable.
I don't wear glasses, so the eye relief of all 4 eyepieces was acceptable to me (from 12mm for the Nagler and Meade s4000, 17mm for the Meade s5000 and 20mm for the Pentax). They were all very comfortable to use with big eye lenses, and it didn't take much effort to know where to place your eye to avoid blackouts or kidney beaning that can be evident with these widefield designs. For those that do wear glasses, the shorter eye relief in the Nagler and Meade Series 4000 will necessitate you to remove your glasses, or you may not be able to take in the full field of view.
All of the eyepieces gave a nice "porthole" feeling, where you could snuggle your eye in close and look around in all directions to take in the whole FOV. The fieldstop on all 4 eyepieces is well defined, as one would expect with premium widefields.
Look and Feel
The build quality of all 4 eyepieces was excellent, and really can't be flawed in any way.
The Pentax and the Series 5000 Meade both had screw adjustable eyeguards, where as the Nagler and the Series 4000 Meade had typical fold down rubber eye cups. Really, I don't find any difference in the eyeguard design - you either use it or you don't. Some people use them to block stray light or know where to place their eye, but in the end the eyeguard design didn't influence me one way or the other. One thing to watch out for though, is to be careful where you hold the Meade s5000, as if the eyeguard is extended and you grab the barrel on the greasy part, you'll get it on your fingers and may accidently transfer it to your lenses. Not to mention it could be slippery. The Pentax does not use such lubricant for its adjustable eyeguard, so it is not an issue.
The Meade s4000 is the only eyepiece of the 4 without safety undercuts in the barrel. I don't find this too much of a concern, as we should always be careful to make sure the eyepiece doesn't fall out onto the ground!
The Meade s4000 and the Pentax have nice plastic bolt cases, whereas the other 2 have typical dust caps. I wasn't a fan of the Meade s5000 top dust cap though, as it was very loose and had a tendancy to fall off.
At the barrel end, all 4 eyepieces were threaded for filters, and obviously the Meade s4000 has a 1.25" and a 2" barrel and can be used in either size focuser without adapters.
From a sheer size and weight point of view, the Meade s4000 is a monster. It's about 3 times the size of the Nagler and twice the size of the Pentax and Meade s5000. It's heavy too, and you will need counterweights when using it on a Dob. The Nagler on the other hand, is small and light and has no such issues with weight. The Pentax and Meade s5000 are a little bigger than the Nagler. The Meade s5000 is a new look, a bit like the Pentax, big and round at the top end. It's an interesting look and quite pretty.
The Meade s5000 comes in a big box, about 3 times the size it needs to be. I can't see any reason for it except for show. The Nagler comes in the usual small Nagler box. The Pentax also comes in a large box supporting the bolt case.
From a purely comfort and ease-of-use point of view, the Nagler wins because of it's small size and weight. Some might like the 'meaty' size and weight of the Meade s4000, but I find it more of an inconvenience than a positive.
Well, the biggest test of any eyepiece is the edge performance in a fast scope like my f/5 10" dob. It's even more important in a widefield design, and extremely important in a premium eyepiece that you're paying $400-$500 for.
The 14mm Pentax XW suffers from field curvature in the last 20% of the FOV. It's quite evident when looking at open clusters or star fields, where the edge looks mushy and out of focus. It can be brought into focus with a slight adjustment of the focus knob, but of course this means the middle is less sharp. It's a known flaw in the Pentax at this focal length. The 7mm and 10mm Pentax do not suffer from this problem. When barlowed, the abberations in the 14mm disappear, and combined with a 2.5x powermate, this combination makes an excellent planetary eyepiece in fast scopes. There is slight astigmatism at the edge of the FOV but it's not usually noticeable due to the field curvature. Chromatic abberation was noted from about 65% out when observing Venus.
The 14mm Meade Series 5000 UWA is a relatively new eyepiece, and so I was anxious to see how it performed after the success and high praise of it's earlier generation Series 4000. Unfortunately I was most disappointed. It exhibited slight field curvature but very evident astigmatism from about 70% to the edge. Chromatic abberation was noted from about 60% out when observing Venus.
The 13mm Nagler Type 6 displayed no field curvature and was sharp right to the edge of the wide FOV. There are basically no apparent edge flaws in this eyepiece. Chromatic abberation was noted from about 65% to the edge when observing Venus.
The 14mm Meade Series 4000 UWA, claimed by some to be the best eyepiece Meade has ever made, is also very good at the edge with no field curvature and virtually no astigmatism. Chromatic abberation was noted from about 70% to the edge when observing Venus.
To summarise edge performance, the Nagler and Meade Series 4000 win hands down. Both sharp right to the edge with no field curvature.
We spend most of our time observing the object in the middle of the FOV, so on-axis performance is a very important characteristic.
The 14mm Pentax is very sharp on axis, giving beautiful pinpoint stars right to the core of 47 Tuc. Contrast is very good. Light transmission also very good and it was easier to resolve the D star in HN40 with this eyepiece. Colour reproduction is very cool and neutral.
The 14mm Meade Series 5000 UWA is also very sharp on axis, which is fortunate considering its edge performance. Contrast not quite as good as the Pentax, and exhibited some glow when viewing Venus. Colour reproduction is slightly warmer than the Pentax.
The 13mm Nagler Type 6, like the other 2 is very sharp on axis, with excellent contrast for such a wide FOV. Colour reproduction is slightly warmer than the Pentax with slightly dampened colour tones.
The 14mm Meade Series 4000 UWA was a tad less sharp than the Pentax and Nagler, but consistently good to the edge. Contrast was also excellent. Colour reproduction was the warmest of them all, giving a slightly yellowish cast.
To summarise on-axis performance, the winners are the Pentax and the Nagler, but only just and the differences are very minor.
John and I observed the following list using the 4 eyepieces, to test how well each performed on different types of objects. The tests were performed over the course of 6 weeks in average seeing and good transparency.
All 4 eyepieces are very good, but which is the best - or, which is the best value for money?
The 14mm Pentax XW is a very nice eyepiece with great eyerelief, very comfortable to use, great light transmission and extremely sharp on axis. The field curvature is it's only flaw but it's a significant one. It's common that some eyepieces have problems at a given focal length, unfortauntely the Pentax has problems at this focal length. As I said above, there are no field curvature issues in the 7mm and 10mm Pentax XW's.
I was quite disappointed with the 14mm Meade s5000 UWA. It's a great looking eyepiece, a nice design and comfortable to use, however the edge performance really lets it down when compared with its previous generation. The Meade s5000 is about 60% of the performance of the Nagler, but you also have to consider it's about 60% of the price as well.
The 14mm Meade s4000 UWA lives up to its reputation of being an outstanding eyepiece, sharp to the edge of the huge FOV and it's a monster. The size and weight are the only negatives of this beautiful eyepiece.
The 13mm Nagler Type 6 is about as good as it gets. There simply isn't a flaw with this eyepiece. Sharp to the edge of a 82deg field, sharp on axis, great contrast, small and light and extremely comfortable to use. Some may say that 12mm of ER isn't enough and that they have problems with it, that may be true but because I don't wear glasses it wasn't a concern for me.
The Nagler really is worth the money for an eyepiece with no flaws. The QA procedures done by Televue are second to none and ensure that you'll get a perfect eyepiece every time. There have been reports of QA problems with the Meade Series 5000 range, I can't comment on this personally but people have claimed to have seen good ones and bad ones.
If you can get a Meade Series 4000 UWA on the second hand market, they're still one of the best eyepieces you'll find. If the size and weight aren't an issue for you, you can't go wrong with this eyepiece as they can represent good value for money at about 70% of the price of the Nagler.
In most areas of comparison, there is little to split the eyepieces and you really have to look closely to find the differences.
Who's the winner then? When comparing all 4 eyepieces for performance and value for money, the 13mm Nagler Type 6 comes out on top. It's a beautiful eyepiece, a consistently high performer in every aspect and if you can afford to own one, they're worth it. They're a great medium power eyepiece for viewing DSO's in a fast dob/newt, and would make a great high power eyepiece in an SCT. The 14mm Pentax XW would also be an excellent choice in longer focal length scopes if a reasonable percentage of your time is spent on high power work such as lunar, planetary and doubles - especially if you wear glasses to observe.
I hope we have provided enough information in this review for you to make an informed decision on your next eyepiece purchase in the 13/14mm focal length. As always, I strongly recommend to try before you buy if you can and test for yourself how the eyepiece will perform in your scope.
Again, many thanks to Bintel for loaning the 13mm Nagler Type 6 and the Meade Series 5000 14mm UWA for the purpose of the reviewReview by Mike Salway (iceman) and John Bambury (ausastronomer). Discuss this review at the IceInSpace Forums.