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Ultima Duo Eyepiece 21mm

Ultima Duo Eyepiece 21mm
Ultima Duo Eyepiece 21mm
Ultima Duo Eyepiece 21mm
Ultima Duo Eyepiece 21mm
Item #: 93445
Your Price: $129.95
Warranty: 2 Years
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  • High performance photo-visual eyepieces quickly switch between observing and imaging
  • Fully multi-coated optics with 8 elements in 5 groups for the best correction of chromatic aberration and field curvature
  • Extra wide 68-degree apparent field of view
  • Full 20 mm of eye relief
  • Integral 42 mm T-adapter threads and threaded barrel for filters

Description

Get a new perspective on the Universe with Ultima Duo, Celestron's versatile new eyepieces that combine excellent optics with a built-in T-adapter for astroimaging.

Enjoy impressive views with a wide 68-degree apparent field of view. Celestron’s fully multi-coated optics increase light transmission and contrast, while blackened lens edges prevent internal reflections. The result is bright, pinpoint stars on a black field. A generous 20mm of eye relief and fold-down rubber eyeguard make Ultima Duo comfortable to use without removing eyeglasses.

Perfect for Imaging

If you’re interested in imaging through the eyepiece, Ultima Duo makes the process quick and easy. Unlike competitors’ eyepieces, you won’t need to spend money on expensive adapters for your camera. The industry-standard 42 mm T-threads are integrated for a direct, secure connection to your DSLR or astronomical CCD camera. Just remove the rubber eyeguard to expose Ultima Duo’s integral T-threads. Then attach your DSLR camera (with compatible T-ring) and you’re ready to capture crystal clear images! Ultima Duo is ideal for imaging bright solar system objects like the rings of Saturn, craters on the Moon, and Jupiter’s Great Red Spot.

Imaging the Moon and planets is even easier with our Smartphone Adapter for Ultima Duo. Unlike “universal” adapters, the Celestron Smartphone Adapter is custom-fit for the Ultima Duo eyepiece line. With this sturdy connection, your smartphone can capture crisp, sharp images of your favorite solar system objects.

Advanced planetary imagers can attach Celestron’s T-to-C Adapter and add a number of high-end imagers to Ultima Duo, including our Skyris and NexImage Burst cameras.

Smart Design for Use in the Field

Ultima Duo’s anodized aluminum body allows it to fit both 1.25” and 2” focusers, so you can use it with almost any telescope with no extra adapters required. A compact body style makes Ultima Duo an excellent choice for use with binoviewers.

The rubber grip rings provide good ergonomics so you can hold onto your eyepiece, even while wearing gloves. The aluminum barrel is threaded to accept 1.25” eyepiece filters and has a safety recess to prevent it from slipping out of the focuser. Each Ultima Duo eyepiece includes cover caps and a protective carry pouch.

This eyepiece is available in 6 focal lengths:

5 mm
8 mm
10 mm
13 mm
17 mm
21 mm

Specifications

Adapter threads 42 mm T-Threads under cup
Apparent field of view 68 degrees
Filter threads Fits Celestron 1.25" filters
Height of eyepieces 95 mm to 120 mm
Lens design 8 element in 5 groups
Optical coatings Fully multi-coated
Width of eyepieces 60 mm

Accessories