• Omni eyepieces offer a quality 4-element Plössl optical design at a super affordable price
• Rubber eyecups provide comfort and increase contrast. Leave them up or fold them down when wearing eyeglasses.
• Beautiful matte aluminum barrels and blackened lens edges prevent internal reflections
• 1.25” barrels are threaded to accept filters ... Read More
Celestron Omni series eyepieces offer a 43º apparent field of view, perfect for the Moon, planets, and a plethora of deep-sky objects. The premium four-element optical set is finished with multiple layers of high-transmission coatings for clear, sharp images. The edges of the optics are blackened for increased contrast.
The Omni eyepiece body is made of aluminum. A two-step anodizing process results in a beautiful matte finish that resists reflections and glare. Each eyepiece in the Omni Series includes a black rubber eyecup. It can be left up or folded down for better observations while wearing eyeglasses. Models with a longer barrel (15mm, 32mm, 40mm) include a rubberized grip for non-slip handling during observing sessions. The insert barrel is threaded to accept 1.25” filters.
Many inexpensive entry-level telescopes are delivered with cheap eyepieces that are sufficient for a first look through the telescope, but soon make you wish for better ones - small field of view or an uncomfortably short eye relief make observing unpleasant. Simple eyepiece designs according to Kellner, Ramsden or Huygens (recognisable by abbreviations such as K, H, or SR) are no longer up to date - even if they are often advertised as "high-performance eyepieces".
With the Omni eyepieces Celestron offers an inexpensive alternative. These are Plössl eyepieces with a four-lens, symmetrical design. Blackened lens edges prevent reflections inside the eyepieces and increase contrast, the multi-coating on each lens allows maximum contrast and light transmission. In addition, each housing is anodised twice to prevent reflections - with other manufacturers you will find reflective surfaces instead.
The eyepieces are pleasantly light and offer a good field of view - it is smaller than the much more expensive wide-angle eyepieces, but there is also far less annoying tunnel vision. The filter thread integrated into the eyepiece sleeve allows you to screw in any 1.25" filter, e.g. to dim the light when observing the moon or to use nebula filters for deep sky observation.
A retaining groove in the plug-in sleeve prevents the eyepieces from slipping out of the focuser and falling to the ground when you tilt the telescope and the clamping screw may have come loose.
The Plössl design
Plössl eyepieces are among the first modern eyepiece designs and can be traced back to the Austrian optician Simon Plössl, who developed them as early as 1860. It was not until the 1980s that the design became popular, as it can be manufactured to a good quality using modern techniques and is far superior to older eyepiece designs. With around 50° of apparent field of view, they are good, versatile eyepieces that can be with you for many years. If you are looking for inexpensive eyepieces that are worth the money, the Celestron Omni eyepieces are a good choice.
Only at focal lengths below about 10mm the interpupillary distance becomes a bit small due to the design - especially eyeglass wearers can use the longer focal length eyepieces in combination with the 2x barlow lens. The Barlow doubles the magnification, while the pleasant viewing behaviour of the longer focal length eyepieces is not changed.
The 40mm eyepiece
The 40mm Omni eyepiece is the longest focal length model in the Omni range and offers the lowest magnification. It is the only one with a smaller field of view than the other models, as the maximum real field of view possible with 1.25" eyepieces is already achieved at about 32mm focal length. If it is only about field of view, the 32mm eyepiece is the better choice. The big advantage of the 40mm eyepiece is that the image is brighter: the more magnified, the darker the image. With the 40mm eyepiece, for example, you can see faint nebulae better than in the 32mm eyepiece, while overlooking the same real section of the sky.
