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Explore Scientific 40mm 52° Argon-Purged Waterproof Eyepiece - 2" - EPWP5240-01

Explore Scientific 40mm 52° Argon-Purged Waterproof Eyepiece - 2" - EPWP5240-01 - Main image
$125.99 $179.99 In stock

Category: Telescope Eyepieces

Explore Scientific 40mm 52° Argon-Purged Waterproof Eyepiece

Experience the extraordinary for the cost of a Plossl with Explore Scientific's 40mm 52° Series Eyepiece! This 40mm eyepiece allows you to see planets appear brighter, star clusters appear sharp, and nebulae details pop. That's the beauty of the 52° Series Eyepieces. EMD coatings to expose faint, deep-sky objects with bright clarity against a dark sky. The flat field even at the edge makes the 40mm eyepiece excellent for averted viewing, which is crucial when observing dim deep-sky objects such as nebulae.

The 2" barrel makes the 40mm eyepiece compatible with many drawtubes and accessories. The textured barrel offers slip-resistant grip, even when wearing gloves.

This Explore Scientific eyepiece features an argon-purged, waterproof exterior that protects internal elements from moisture. In fact, internal elements will remain as pristine as the day they were assembled. This also makes cleaning the 40mm 52° eyepiece effortless. There is no risk of cleaning solution migrating from the top of the lens and seeping around edges to be trapped in between elements.

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Customer Reviews (4.4 / 5 · 5 reviews)

Steven ★★★★★

Argon purging is the reason I picked this over cheaper 2-inch options, and it’s held up beautifully through dewy nights without a hint of fogging. The 40mm focal length gives me gorgeous, low-power sweeps of the Milky Way, and the weight feels solid without being a backbreaker.

Jacob Z. ★★★★★

The 40mm focal length gives me incredibly immersive views of the Orion Nebula — I can see the entire trapezium cluster in one field. The argon purge gives me real peace of mind during those dewy nights. This thing feels built to last forever.

Jacob ★★★★☆

The 40mm focal length gives wonderfully wide, immersive views of the Milky Way, easily fitting the entire Pleiades cluster into the field. My only small gripe is the eye relief feels a bit tight for eyeglass wearers, but the sharpness across the 52° field more than makes up for it.