Inspired by the venerable Nagler design, the 7-element/5-group lens configuration employed in the Tele Vue Nagler Type-4 22mm Eyepiece maintains the contrast and clarity of the original design, and optimized for deep-sky viewing.

Built to Tele Vue's exacting standards, the Type-4 features anti-reflection fully multi-coated optics to improve brightness, color rendition, and contrast. The proprietary click-stop Instadjust eyecup assures proper space between the eye and lens for eyeglass users, while blocking interfering stray peripheral light from distracting from the viewing experience for those not wearing eyeglasses. Despite its moderate focal length, the optical properties allow it to maintain an impressive 82° wide apparent field of view, and a long 19mm eye relief that provides ample space between the lens and eye to prevent accidental contact that can interfere with views. This model has a large 2" barrel diameter to make it even more comfortable to view through, and a textured rubberized grip for sure handling.

22mm Focal Length    82° Field of View    2" Diameter Barrel    Fully Multi-Coated Optics    7-Element/5-Group Lens Design    Slip-Resistant Textured Surface    Instadjust Click-Stop Eyecup

Related Questions and Answers

Q: 1. Is this a good eyepiece and is it compatible with the Celestron Nexstar 105 GT telescope?

A: Televue Panoptics are excellent eyepieces. Very sharp, clear images. To determine if an eyepiece is compatible with your telescope you first need to calculate your telescope's Maximum True Field of View, then calculate the eyepiece's True field of View. Eyepieces that have a True Field of View greater than your telescope's Maximum True Field of View will cutoff the image and have chromatic aberrations around the edges. Generally speaking, it does not hurt to go a little over tFOV with quality eyepieces, but the more the eyepiece's tFOV is over the telescopes's max tFOV more of the image is cutoff and the worse the chromatic aberrations get around the edges.There are several very good free eyepiece calculators available on the web to calculate Max tFOV, and help determine eyepiece compatibility.

Q: 2. Are the Delos eyepieces par-focal?

A: Yes they are par focal with many other Televue eyepieces. Go to the televue site and look at the chart of eyepiece specifications. Scan the column 4G . Eyepieces with the same letter in that column are parfocal. So most of the Delos ep's have the letter B . You will see that some other types of TV eyepieces also have the letter B . All those are par focal.

Q: 3. what is the percentage of distortion.....?

A: It would really all depend on the Telescope you have. Unfortunately I do not have that type of information, my apologies.

Q: 4. B&H review note says Delos 8mm eyepiece is parfocal with GROUP B, what is that?

A: That is referring to compatible Parfocal Group 'B' Eyepieces. Here is a list of those eyepieces: 8 - 32mm Plossl eyepieces All DeLite eyepieces 19 & 24mm Panoptic eyepieces 3.5 - 12mm Delos eyepieces 16mm Nagler 5 eyepiece All 1.25" Nagler 6 series eyepieces

Q: 5. Hello,Is this lens compatible with the Celestron 6SE telescope?Many thanks

A: I bought the lens about a month but have no chance to view through it yet. However I did try fitting it to my Celestron 8SE telescope which has a 1.25 diagonal and I did not have any problem.

Q: 6. Is astigmatism an issue with Nagler zoom, which result in very small exit pupil dimensions? I hope not to wear eyeglasses, due to only 10mm eye relief on this zoom. Thanks.

A: As one can see reading the reviews on the Tele Vue Nagler Planetary 3-6mm Zoom Eyepiece (1.25"), there does not appear to be an astigmatism issue. Users with glasses say the eye relief works for them.

Q: 7. are the Delos series eye pieces par-focal?

A: Yes it is. This is parfocal with Tele Vue Group B eyepieces so no refocusing is required when switching between eyepieces within the group.

Q: 8. What I feel that needs to be better explained about eyepieces and focal lengths as in 6mm or 25mm is that the opening is tiny for 6 mm as compared with 25mm that is wider . The lower the focal length the difficult it gets to train your eye throughthe opening due to its tiny opening. My child experience with my first kid telescope that came with 6mm and 25mm eyepieces told me that 25mm is more enjoyable to use despite lower magnification than the higher magnifying 6mm which is so restrictive in the opening for my eye to keep peeking through as steadiily as I can. I think that a minimum of 10mm is acceptable to me or maybe 12mm. . Am I correct?

A: Yes that is correct. 10 or 12mm will be okay. It also depends on how large of an aperture your scope has. The bigger front opening of the scope the brighter the image.

Q: 9. how do you know what type of eye piece works best with your telescope? Is there a rule or formula to calculate it, if you work with refractor/reflector, and if you add a barlow lens?

A: For example, to calculate maximum power of a telescope, a 90mm diameter scope will have a 180 maximum power. Please call in for further info .

Q: 10. What's the condition of Ethos EP?

A: The USED Tele Vue Ethos 13mm Ultra Wide-Angle Eyepiece (1.25"/2") Used Cat #2699851 • MFR #ETH-13.0 Condition: 9 Minor surface marks Very good condition; overall looks clean but may have minor signs of use/surface marks. There are no scratches or blemishes to the optics.