Tele Vue 17.3mm 1.25" 72° field Delos


Availability: In stock

This new 72° field TeleVue 17.3mm Delos eyepiece brings the superb image quality and color neutrality of the renowned TeleVue Ethos eyepieces to medium power planetary, lunar, and deep space observing . . .
Our Product #: TD17
TeleVue Product #: EDL-17.3
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Product Description

The 17.3mm TeleVue Delos is a "do-it-all" eyepiece designed for medium power/high contrast solar system and deep space observing with all telescope types and sizes. It has a long 20mm eye relief that makes it ideal for eyeglass wearers. It is designed to use the TeleVue Dioptrx astigmatism-correcting lenses, so you can even observe without your glasses, should you so desire.

There is an adjustable height eyeguard with a soft rolldown eyecup to shield the eye from ambient light (from a neighbor's security light, for example) and improve the image contrast. The eyeguard height can be locked in place at any point desired.

Coming from the same optical designer who created the famed TeleVue Ethos 100° field eyepieces, the 17.3mm Delos has all the virtues that astronomers have come to expect from an Ethos: high contrast, a neutral color balance, and full field sharpness. Astigmatism is well-controlled, as is field curvature, lateral color, and angular magnification distortion correction. In addition, the Delos has low pupil sensitivity (kidney bean effect) for daytime use.

The 17.3mm Delos has a 1.25" barrel that is threaded for standard 1.25" eyepiece filters. A safety groove is machined into the chrome barrel to engage your focuser thumbscrew. This will help prevent the eyepiece from falling should the thumbscrew accidentally loosen while observing. The main eyepiece barrel is narrow enough to comfortably use a pair of 17.3mm Delos in a binoviewer. Rubber grip rings provide a sure grip in cold weather when wearing gloves or mittens. Dust covers are provided for both ends of the eyepiece.

Tech Details

Barrel Size 1.25"
Eye Relief 20mm
Field of view 72
Focal Length 17.3mm
Weight 14.4 oz.
Warranty Limited Lifetime


Review by:
Generous eye relief allows many eyeglass wearers to make full use of this eyepiece making it great for sharing awesome views with the public. Do be aware of the increased weight over a standard Plossl. Enjoy. (Posted on 10/31/2019)
Review by:
This is a fine eyepiece, with slightly better contrast and far better eye relief than a 15mm Panoptic. A good higher power companion to the classic 24mm Panoptic, which has close to the same AFOV. (Posted on 1/9/2019)
Review by:
I use the 17.3 Delos primarily for planetary viewing with my 12" Meade ACF OTA. It provides high contrast sharp views at just the right magnification. The generous eye relief and wide apparent field make for very pleasant viewing. The large eye lens gives one the impression that this is a high quality product. (Posted on 12/11/2018)
Review by:
I bought this eyepiece from astronomics along with the 6mm, 4.5mm and 3.5mm iterations. They all came quickly and were well packaged. The eyepiece is beautiful and feels quite solid yet not overly heavy. The twist-up eyeguard is nicely done and locks in place. The eye relief is comfortable and the entire field is easily visible without having to have your eye nearly touching the top of the lens. The field, while not as large as a Nagler or Ethos, is more comfortable to me and does not feel at all constricting. This eyepiece is not as tall as the shorter focal lengths so there should be no problem storing it vertically in your case. This eyepiece will not disappoint. (Posted on 12/9/2018)
Review by:
This is a wonderful eyepiece. It is sharp as a tack clear to the edge. It is my favorite mid-range eyepiece and never disappoints. It has very good eye relief which is important to me. Perfect for my C11.
I highly recommend it! (Posted on 12/8/2018)
Review by:
This is an amazing eyepiece. Even in my humble ST-80, the Delos 17.3 presents a flat field, and ink-black backgrounds. It is a perfect initial eyepiece to scan the Milky Way before switching to a higher power eyepiece. I wear glasses and the eye relief allows me to keep them on, though with the quality of optics, I can manage going without them more often than not. (Posted on 11/26/2018)
Review by:
One reason to like the Delos line is for their adjustable eyecup. You basically can change the eye relief from 20mm down to about 8mm by sliding the upper part of the eyepiece body. It is rigidly locked in place by tightening the two knurled rubber rings. Without glasses my preference is about 12mm. This is helpful when observing with friends who must wear glasses -- everybody gets a custom fit. (Posted on 11/1/2018)
Review by:
Sharp to the edge, great eye relief for glasses wearers, and great ability to personalize with adjustments built into the barrel plus the eye cup. (Posted on 10/6/2018)
Review by:
If you can get a 25% discount it is worth buying for the eye relief if you wear glasses. It is nice to use with my 1500mm 12" dob for 87x magnification. Keeping the weight under 1# is max for eyepieces not twisting a C8 diagonal loose from the back. (Posted on 10/6/2018)
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