Explore Scientific 52° Series Argon Purged Waterproof Eyepiece (40mm)

The Explore Scientific 52° Series 40mm Waterproof Eyepiece is the longest focal length in this product line, offering the longest eye relief. It is also the only 2.0-inch O.D. eyepiece in the 52° Series. Explore Scientific has three 40mm eyepieces in their collection, with the other two being the 40mm 62° Series and the 40mm 68° Series.

At this 40mm focal length, this eyepiece is well-suited for deep sky observers who strive to reach the faintest observable limits of their telescopes. The expansive true field of view makes it perfect for observing deep sky objects such as the Andromeda Galaxy, the Rosette Nebula, as well as large star clusters and comets.

With an apparent field of view of 52 degrees, these eyepieces offer exceptional value. They are excellent flat-field multi-element oculars that can significantly enhance your visual astronomy experience, outperforming comparably priced Plössl eyepieces.

Another key benefit of these 52° Series eyepieces is the excellent contrast and ease with which you can observe using averted vision. This technique, which involves gazing slightly to the side of the target object, is particularly helpful when observing faint celestial bodies, as it allows the image to fall on the more light-sensitive part of the eye.

The Explore Scientific 52° Series 40mm Waterproof Eyepiece boasts the following specifications:

Item Number: EPWP5240-01 Focal Length: 40mm Length: 96.6mm Width: 61.8mm Weight: 385.5 grams (13.6 oz.) Barrel Size/Type: 2.0" O.D. / Double Taper Eye Relief: 27.1mm Field Stop Diameter: 36.3mm Coatings: EMD (Enhanced Multi-Layer Deposition) on all lens-to-air surfaces Lens Elements/Groups: 4 Elements in 2 Groups; Edge Blackened Filter Thread: Fits Standard 2.0-inch Diameter Threads (48mm x 0.75mm) Waterproof: O-Ring Sealed, Argon Gas Purged; Tested Under 1 Meter of Water for 30 Minutes Eyecup: Removable Flip-Down Style Soft Silicone Rubber Lens Caps: Slide-on Top and Bottom Materials: Optical Glass, Aluminum, Steel, Silicone Rubber

Explore Scientific is an optics company based in Springdale, Arkansas, dedicated to providing enthusiasts of all skill levels with the tools and guidance they need to explore the skies and the world around them. The company designs, manufactures, markets, sells, and distributes high-quality observation instruments and accessories, including telescopes, eyepieces, microscopes, and binoculars.

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