William Optics Zenithstar 81 f/6,9 OTA FPL53 doublet APO, 2,5" R&P focuser in gold (SKU: A-Z81GD)

The William Optics Zenithstar 81 telescope is a highly renowned and versatile instrument suitable for both astrophotography and visual observations.

This exceptional refractor is designed to deliver incredibly sharp images with impeccable chromatic aberration correction, thanks to its advanced and precisely crafted optics. The telescope features a two-element construction with an air gap, incorporating an ED (Extra-low Dispersion) element made of FPL-53 glass, a synthetic fluorite material produced by the esteemed Japanese company Ohara. FPL-53 glass boasts an incredibly high Abbe number of 94.94, making it superior in terms of optical performance compared to crystalline fluorite. Additionally, this material offers enhanced chemical stability and ease of processing. The lens surfaces are further enhanced with the SMC coating, which minimizes light reflections and improves contrast. Despite being a two-element design, this telescope is often referred to as a full-fledged apochromat due to its exceptional performance.

The telescope tube is securely mounted on precisely manufactured clamps that feature a Vixen socket, allowing for the attachment of a finder or guider. It also includes a versatile Vixen/Arca-Swiss foot for seamless mounting on a mount or photographic tripod.

Key Features of the William Optics Zenithstar 81 Telescope:

• Two-element construction with an air gap and low dispersion element made of Japanese FPL-53 glass (synthetic fluorite).

• Solid rack & pinion focuser equipped with coarse and fine focus adjustment knobs.

• CNC technology used for optical tube clamps, ensuring a sturdy and precise grip.

• Mounting foot compatible with Vixen and Arca-Swiss sockets, facilitating easy attachment to a mount or photographic tripod.

Technical Specifications:

• Telescope optical system: ED doublet with air gap.

• Lens diameter: 81 mm.

• Focal length: 559 mm.

• Aperture ratio: f/6.9.

• Maximum usable magnification: 162x.

• ED lens material: FPL-53 glass (Ohara, Japan).

• Optical system coating: SMC coating.

• Compatible sensor sizes: APS-C, full frame.

• Focuser: 2.5".

• Type of focuser: Rack & pinion with dual-speed capability.

• Thread for connecting the flattener/focal reducer: M63.

• Finder foot: Vixen.

• Mounting bracket: Vixen/Arca-Swiss.

• Tube length (folded): 460 mm.

• Tube length (unfolded): 560 mm.

• Tube weight: 3.5 kg.

• Tube finish: Plain white.

Included Accessories:

• William Optics Zenithstar 81 refractor (white-gold color scheme).

• Dew shield.

• Bahtinov mask with mount.

• Lens cap.

• Clamps with Vixen/Arca-Swiss foot.

Warranty:

The William Optics Zenithstar 81 telescope comes with a 24-month guarantee, ensuring peace of mind for the user.