Quotes from review of 10mm, 4.5mm, & 14mm Delos on Alpha Lyrae website.

• The stunningly flat field and lack of optical aberrations really allow clusters to shine and galaxies and nebulae are resplendent.
• [I]t is rare I use any other eyepiece for deep sky observing anymore.
• Quite simply, the planetary performance matches the very best dedicated planetary eyepieces I have ever used such as the TMB Super Monocentric.
• [T]here is also an indescribable quality which makes them a very easy and relaxing eyepiece to use.

Excerpt from Delos 17.3mm review in Astronomy Now magazine.

Examining the stars of the Pleiades served up by the 17.3mm Delos, I was immediately struck by the pinpoint star images right to the edge of the field-of-view. Contrast was superb. Nor could I detect any signs of off-axis distortions.

Sky & Telescope Hot New Product for 2012 Award

More Than Expected (Delos 6- and 10-mm)
And while the 20 mm of eye relief make them attractive for those who observe wearing eyeglasses, it was the "distinctly pleasurable" observing experience that most impressed our reviewer. When it comes to eyepiece design, The Delos seems to have hit all the sweet spots.

Excerpt from ATT review of Delos 6- & 10-mm eyepieces:

Wide-Field Eyepieces That Pack a Planetary Punch

With the Delos, the eyepiece simply "disappears" and allows the observer to observe. I could find nothing whatsoever to complain about; the "twist and tighten" eye relief adjustment feature is the best I've ever seen in any eyepiece, and the optics are essentially perfect. Tele Vue somehow always finds a way to continuously improve upon their eyepieces and the Delos is certainly no exception. Bottomline: If you're in the market for a planetary eyepiece, you owe it to yourself to consider the Tele Vue Delos.

Review of the 6mm & 10mm Delos Eyepieces from Astronomy Magazine, December 2011

• Contrast was excellent - right up there with some of the best planetary eyepieces I've ever used.
• I searched but saw no internal reflections or scattering in either eyepiece.
• The flat field the Delos eyepieces produce really made star fields pop. Open clusters epitomized the old standard "diamonds on velvet". Stars on and off axis showed no sign of astigmatism.
• Tele Vue has constructed an eyepiece that stands with the best deep-sky and planetary eyepieces on the market.

Excerpts from Sky & Telescope, June 2011, review of Delos eyepieces:

WHAT WE LIKE:

Essentially perfect optics
"Immersive" observation experience

WHAT WE DON'T LIKE:

Trying to nail down why the observing experience is so pleasurable.

I spent several nights viewing the Moon, Saturn, stars and nebulae with a variety of telescopes … .

The Delos eyepieces are "easy to look through … . They have flat fields, delivering absolute pinpoint stars from edge to edge with no hint of color aberration. The view, especially during the daytime, is very pure with no noticeable color tint. And there wasn't a hint of ghosts or reflections, even with the brightest stars".

"What caught me a bit off guard, however, was something that's best described as the observing experience. It was distinctly pleasurable."

"I have the sensation of looking out of a circular window rather than into an eyepiece."