At a Glance
10mm
Focal Length
72°
Apparent FOV
20mm
Eye Relief
1.25"
Barrel Size
Score Breakdown
Overview
The Tele Vue Delos 10mm sits in a sweet spot for visual observers who want a high-performing mid-range eyepiece without the bulk of wider-field designs. At 10mm focal length, it delivers useful magnification across a broad range of telescope focal ratios, making it a practical choice for planetary detail, globular clusters, and tighter deep-sky targets. Where this eyepiece genuinely stands out is its 20mm eye relief.
That is a generous figure for a 10mm eyepiece, and it matters considerably if you wear glasses or simply find yourself fatiguing during long sessions at the eyepiece. The 72-degree apparent field of view is wide enough to give good spatial context around your target without pushing the design into territory where edge correction typically suffers. Tele Vue's proprietary multi-coatings help preserve contrast, which you will notice most when working on low-contrast objects like planetary cloud bands or faint nebulosity.
Build quality is consistent with Tele Vue's reputation: rubber grip rings, fold-down eyeguards, blackened lens edges, and a secure undercut barrel all speak to long-term durability. At $438, this is a significant investment for an amateur. However, for observers who are tired of compromising on comfort or optical consistency, the Delos 10mm holds up as a genuine long-term eyepiece.
Key Features
- 20mm eye relief makes extended viewing comfortable, including for eyeglass wearers
- 72-degree apparent field of view balances immersion with effective edge-to-edge correction
- Fully multi-coated optics with high-index glass help maintain contrast on demanding targets
- Blackened lens edges reduce internal scatter, which benefits planetary and high-contrast viewing
- Fold-down eyeguard and rubber grip ring add practical comfort during late-night sessions
- Undercut barrel provides extra security when locked into focusers or diagonals
- Compatible with standard filter threads, so you can use your existing narrowband or moon filters
Specifications
| Focal Length | 10mm |
| Apparent FOV | 72° |
| Eye Relief | 20mm |
| Barrel Size | 1.25" |
| Design | Modified Nagler |
| Elements/Groups | 8/4 |
| Series | Delos |
| Coating | Fully Multi-Coated |
| Waterproof | No |
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Amazon Reviews
I couldn’t ask for a better eye piece. Super sharp great eye relief
There are two words to describe this eyepiece: AWE SOME!!! The field of view is wide (82 degrees) and eye relief is 20 mm...nearly an inch. I'm accustomed to 10mm eyepieces being like looking through the center of a washer. This one is just as sharp, edge to edge as my Televue 16mm II, but with addi...
After using cheapo starter eyepieces over the last 20 years on an old 8 inch SCT, I decided to upgrade when I bought a new 10 inch Dobsonian. Wow, what a difference. Flat field and stars sharp right to the edge. Much larger field of view as well. I noticed that deep sky objects not visible with a si...
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