Using the Explore Scientific 120° Ar purged Eyepiece 9mm is a totally unique experience. Never before has an eyepiece been created with such a large apparent field - the clarity and correction of which has to be seen to be believed. Other eyepieces may claim to offer large expansive views, but pale in comparrison to this incredible Explore Scientific occular.
The Explore Scientific 9mm 120° Series™ eyepiece really is in a class by itself. The 120° apparent field of view is unlike anything you have experienced before. Normally, when we look through hyper wide field eyepieces, we see a huge swath of the night sky at low magnification. With the 9mm 120°, however, you see even more universal real estate, but you also see the main attraction, whether it is a nebulae, a galaxy, or a star cluster, close up and personal. In our opinion, it is the best of both worlds.
With such a wide field, you will also notice that objects stay in the field of view for a long time. This is especially noticeable when your telescope does not have a drive, like a Dobsonian.
Another great benefit of hyper-wide eyepieces is the ease with which you can gaze, not directly at an object, but slightly to either side. This skill, called using averted vision, is especially helpful when observing faint objects, because using averted vision puts the image on a part of your eye that is more sensitive to light, allowing you to see fainter images.
Explore Scientific 120° Eyepiece Highlights
Optimized Optical Design The Explore 9mm 120° Series eyepiece is optimized through each design, fabrication, and testing process to produce flat-field images that have high contrast and resolution.
Exotic Glass Combinations for Optimum Results The Explore 9mm 120° eyepiece is constructed of 12 lens elements in 8 groups, and are fabricated from combinations of Dense Crown, Light Crown, Dense Flint, and Lanthanum optical glass.
Durable Coatings & Finishing Touches Each element in your Explore Scientific 120° eyepiece is fully multi-coated, resulting in bright, sharp images, and every element has blackened edges to reduce internal reflections and increase contrast.
Waterproof, Fog-Proof Housing - the internal optics of the 9mm 120° eyepiece is housed in an Argon gas-purged, waterproof barrel that keeps it as pristine as the day it was manufactured. Cleaning is much easier, and there is no need to worry about water or fluid becoming trapped in between elements due to rain, spills, heavy dew, or getting over-enthusiastic with lens cleaning fluid.
Hyper-Wide Field Experience The 120° experience is different than that of more conventional eyepieces. A hyper-wide field of view means you can see more of the night sky at once, allowing you to observe larger or closer objects in their entirety, or to easily use inverted vision to capture faint photons of light.
Tapered 2" Barrel for Extra Security The insert barrel of each eyepiece is double-tapered to allow smooth insertion to, and removal from, a telescope's eyepiece holder or diagonal, however the wide dimension of the taper helps prevent the eyepiece from falling out of the telescope should the set-screw holding it in place become loose. The 2" barrel is threaded to accept standard screw-on filters.