- Explore Scientific 120° Series Waterproof Eyepieces -


purchase description field stop dia eye relief size weight
Dealer or Buy Now #EP12009-01 - 9mm 120° WP Eyepiece; 2.0-inch 15.7mm 12.5mm L=145mm x W=60mm 602 grams; 21.2 oz

Go Hyper-Wide & Experience the Vastness of Space Like Never Before


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 or a refractor on a grab and go mount like the Explore Scientific Twilight I. 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 a 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.


Optional Focal Extenders for Extra Magnification Explore Scientific makes a wide variety of eyepiece focal lengths, allowing a change in magnification for just about any observational study you can think of. However, if you would like to get "double duty" out of the eyepieces in your accessory case, while still retaining the eye relief of that eyepiece, use Explore Scientific Focal Extenders.



Explore Scientific Eyepieces are Gas-Purged and Waterproof to Make Cleaning Easy


Cleaning Waterproof Eyepieces


While a few dust particles on optics will not affect visual or photographic performance, there comes a time when your eyepiece will become dusty or dirty enough to affect contrast. When cleaning your standard eyepieces great care must be taken to keep water or other liquids from seeping into the elements, but not so with Explore Scientific Waterproof Eyepieces. Since our eyepieces are completely waterproof and fog-proof (we test them by submerging in one (1) meter of water for thirty minutes), they can be washed under running water, and optical cleaning solutions can be applied directly to the optics without worry. Remove the soft rubber eyecup and use the same techniques that you would use to clean a telescope's primary mirror. After a final rinse in pure distilled water and dried with compressed air, you can clean these eyepieces with professional results to the very edges of the external lens elements.

Explore STAR Extended and Transferrable Life of the Product Warranty


Explore STAR Warranty


We are always striving to improve the quality of Explore Scientific eyepieces and to enhance your experience as a user of our products. This is why we created the Explore STAR Transferrable Extended Life-of-the Product Warranty Program.


For as long as we manufacture a product it is under warranty, no matter how many times it is sold or traded to another individual. And when we stop manufacturing a given model (which is the end of the Life of the Product), we will extend the warranty automatically for another five years.


Learn More about Explore STAR Warranty

Review of Explore Scientific's Focal Extenders


Reviews & Testimonials


Read reviews and comments from experts and owners to determine if an Explore Scientific eyepiece is the right tool for you:


The latest review of the Explore Scientific 9mm 120-degree eyepiece from The BBC Sky At Night Magazine.


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