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AstroZap Full Aperture Aluminum Bahtinov Focus Mask for 11.5" - 14.5" OD Telescopes - AZ504

AstroZap Full Aperture Aluminum Bahtinov Focus Mask for 11.5" - 14.5" OD - Main image
$65.18 $86.9 In stock

Category: Telescope Accessories

AstroZap Bahtinov Focus Mask for 11.5" to 14.5" OD Telescopes

AstroZap's Bahtinov is a full-aperture focusing mask that has been manufactured with lightweight aluminum for effortless application. The bahtinov features grommets that can be easily modified for telescopes with an outer diameter of 2.5" - 5.5" (292 mm - 368 mm). The thin construction allows for fantastic performance.

AstroZap Bahtinov Focus Masks

All observers and imagers are aware of the fact that sharp focus is necessary for making the most out of your valuable time with the telescope. The Bahtinov-style mask has now passed the Hartmann mask in popularity due to its novel diffraction pattern that enables higher accuracy for detecting the ideal focus point. For observational light side astronomy, the Bahtinov mask allows quicker, more exact focusing when switching eyepieces. For imaging (dark side astronomy), where camera focusing is crucial to achieving the finest images, the Bahtinov mask makes it easy to find the point of optimal focus without having to guess and enables quick adjustments when switching filters or fine-tuning focus as your imaging session persists into the night.

The Astrozap Focusing Mask is proudly made in the United States from solid sheet aluminum, contrary to plastic focusing masks available from other manufacturers that are not anywhere near as durable. Powder coating helps maintain its appealing looks by preventing corrosion. AstroZap carries several sizes of focusing masks to fit telescopes with the most common outside diameters. Plastic screws mounted in rubber grommets are adjustable in order to conform to the exterior of the optical tube, keeping the screen in place while avoiding scratching or otherwise causing harm to the telescope's finish. The unique Bahtinov diffraction pattern utilized by this AstroZap Focusing Mask enables consistently optimal focus.

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.8 / 5 · 5 reviews)

Christopher R. ★★★★★

Fits my 12-inch scope perfectly and the Bahtinov spikes are crisp and sharp. I got a perfect focus on my first try with a bright star, way faster than my old method.

Thomas ★★★★★

The aluminum construction feels solid but lightweight, and sliding it onto my 12" telescope was effortless. The diffraction pattern gave me pin-sharp stars in seconds—huge improvement over guessing focus by eye.

Richard E. ★★★★★

Finally got sharp focus on my 11.5" scope with this mask—the full-aperture design covers the entire opening without any gaps. It's lightweight aluminum, so it doesn't add any noticeable weight to the front end.