Explore Scientific 17 mm 92° Waterproof 2″ Eyepiece
The 17mm 92° Series™ eyepiece by Explore Scientific is part of an ultra-wide class of oculars that will revolutionize your astronomy observations. Enjoy the picturesque wide expanse of inky black sky you will see in the 92° Series eyepiece. With non-driven telescopes, you will benefit from viewing objects that stay in the field of view for a long time before any adjustments are necessary. The Explore 17 mm 92º Eyepiece has a generous 20mm of eye relief. This Explore Scientific eyepiece is designed to increase the comfort level for long nights of observing as well as give you an amazingly immersive visual experience.
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.
The Explore 92° Series eyepieces come with a removable and foldable soft silicone rubber eyecup for the comfort of the observer, and as experienced astronomers know, eye comfort is critical when trying to observe at the visual limits of the telescope.
By making the eyepiece body Argon-purged, the eyepiece’s internal elements will remain as pristine as the day they were assembled. Argon atoms are “ larger” than that of Nitrogen and therefore they are less likely to “leak” or diffuse their way through the seals over the life of the eyepiece. The atomic radius of Argon is larger than Nitrogen by 0.13 angstroms and has a larger atomic volume by 11.2 cubic centimeters/molecule. Argon also has superior inertness vs Nitrogen (i.e. forming few or no chemical compounds with other elements) that prevents adverse reactions with eyepiece components and therefore extends the longevity of the internal components and also prevents chemical reactions with other elemental contaminants that may be introduced through a weakened seal. And finally, because Argon is less conductive than Nitrogen, Argon cools slower thereby buffering the effects of rapid temperature changes of the optics.
The sealed, dry environment is impervious to internal fogging and contaminants such as fungus growing in between the lens elements. Explore Scientific’s waterproof eyepieces are easier to clean, and there is no risk of cleaning solution migrating from the top of the lens and seeping around the edges to be trapped in between elements. To ensure a perfect seal, Explore tests every eyepiece in one meter of water for 30 minutes.