[28mm]
[16mm]
[24mm]
[34mm]
[20mm]
Using advanced computer design, combinations of low dispersion and high refractive index optical glasses, and durable multilayer deposition coatings, Explore Scientific 68° Series Argon-Purged Waterproof extreme wide field eyepieces are optimized to produce high contrast, high resolution, and superior flat field characteristics. The visual effect of these eyepieces with their long eye-relief and their 68° apparent field is truly a full-immersion experience. The 68° Series eyepieces are parfocal (meaning they focus at near the same point regardless of the focal length you select) and 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 waterproof eyepiece 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 of heat 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 getting between the lens elements. Our waterproof eyepiece is easier to clean, and there is no risk of cleaning solution migrating from the top of the lens and seeping around edges to be trapped in between elements. To insure a perfect seal we test every eyepiece in one meter of water for 30 minutes.
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68 Degree 16mm Eyepiece | 68 Degree 20mm Eyepiece | 68 Degree 24mm Eyepiece | |
Item Number | EPWP6816–01 | EPWP6820–01 | EPWP6824–01 |
Focal Length | 16mm | 20mm | 24mm |
Length | 61.9mm | 69.6mm | 75.6mm |
Width | 43.2mm | 50.3mm | 56.2mm |
Weight | 5.5oz; 158g | 8.7oz; 247g | 11.6oz; 329g |
Barrel Size | 1.25" | 1.25-inch | 1.25" |
Eye Relief | 11.9mm | 15.3mm | 18.4mm |
Field Stop Diameter | 18.2mm | 22.8mm | 27.2mm |
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68 Degree 28mm Eyepiece | 68 Degree 34mm Eyepiece | 68 Degree 40mm Eyepiece | |
Item Number | EPWP6828–01 | EPWP6834–01 | EPWP6840–01 |
Focal Length | 28mm | 34mm | 40mm |
Length | 91.4mm | 100.8mm | 114.2mm |
Width | 61.3mm | 69.6mm | 80.3mm |
Weight | 16.1oz; 458g | 24.1oz; 685g | 35.2oz; 998g |
Barrel Size | 2.00" | 2.00" | 2.00" |
Eye Relief | 21.6mm | 26.4mm | 31mm |
Field Stop Diameter | 31.8mm | 38.6mm | 45.5mm |
To discover what magnification you will have with a given eyepiece you must know two numbers. First, take your telescope’s focal length in millimeters, and divide this number by the focal length of your eyepiece (this will be written in millimeters on the eyepiece).
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52 degree eyepiece family | 62 degree eyepiece family | 82 Degree Eyepiece Family | 92 Degree Eyepiece Family | 100 degree eyepiece family | |
FOV | 52 Degrees | 62 Degrees | 82 Degrees | 92 Degrees | 100 Degrees |
Based out of Springdale, Arkansas, Explore Scientific is an optics company that has been on a mission for the last decade to provide enthusiasts of all skill levels the tools and guidance they need to explore the skies above and the world around. The company is involved in designing, manufacturing, marketing, selling and distributing high-quality observation instruments and accessories such as telescopes, eyepieces, microscopes and binoculars.