The jump from 42mm to 50mm objectives makes a real difference at dawn and dusk — more light in, brighter image out. The Alpen Chisos 10x50 pairs that extra light-gathering with ED glass and PXA phase-coated prisms for the color accuracy and edge sharpness that 10x magnification demands, all in a magnesium chassis built for serious field use.

Key Features

• 50mm Objective Lenses — Gathers noticeably more light than 42mm models, keeping views bright and detailed in the low-light conditions where wildlife activity peaks.
• ED Glass — Extra-low dispersion elements eliminate chromatic aberration at 10x, keeping plumage colors true and fine detail sharp against bright sky and backlit canopy.
• PXA Phase-Coated BaK-4 Roof Prisms — Phase correction preserves resolution and contrast edge-to-edge for confident ID work at distance.
• Fully Multi-Coated Optics — Every air-to-glass surface treated for maximum light transmission and minimal glare.
• 6.5-Foot Close Focus — Tight enough for feeder birds, butterflies, and wildflowers — versatile across near and far subjects.
• Lightweight Magnesium Housing — Durable yet comfortable for all-day carry with textured grip panels.
• Waterproof & Nitrogen-Filled — Sealed against rain and humidity, internally fog-proof through rapid temperature swings.
• 18mm Eye Relief with Twist-Up Eyecups — Comfortable viewing for glasses wearers across extended sessions.

Ideal For

• Birders who want 10x reach with extra brightness — 50mm objectives outperform 42mm in dawn, dusk, and canopy shade where plumage ID depends on available light.
• Hunters who glass ridgelines and treelines in marginal light and want ED color accuracy to distinguish game from terrain.
• Wildlife observers who work from blinds or fixed positions and value brightness over ultralight portability.
• Astronomy enthusiasts looking for a step up from 42mm for brighter views of the Milky Way, open clusters, and bright nebulae.
• Glasses wearers who need comfortable eye relief without sacrificing field of view.