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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.

William Optics Zenithstar APO Refractors

William Optics Zenithstar refractors are compact apochromatic doublets for portable astrophotography and visual observing. This collection includes the Zenithstar 61II APO, a small travel scope, and the Zenithstar 81 WIFD with internal focusing.

Dedicated correctors are also here: the adjustable Flat61 flattener and Flat61R reducer flattener for the Z61, and the Flat73A flattener and Flat73R reducer flattener for the Z73, which let you choose between native and reduced focal length.

Filters

$278.00 - $278.00
$278.00
$278.00 - $278.00
$278.00

William Optics Adjustable Flat73A for Z73

WO-P-FLAT73A
1 in stock

Designed specifically for the William Optics ZenithStar 73 APO Delivers a 1.0x, perfectly flat field across full-frame sensors Connects to the Z73...

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$278.00 - $278.00
$278.00
$278.00 - $278.00
$278.00
$674.98 - $697.00
$674.98 - $697.00
$674.98 - $697.00
$674.98

William Optics Zenithstar 61II APO

Options available

61mm Aperture Apochromatic Doublet Refractor Ohara FPL-53 ED Glass Element Fast f/5.9 Focal Ratio for Wide-Field Imaging Includes Flat61A Field Fl...

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$674.98 - $697.00
$674.98 - $697.00
$674.98 - $697.00
$674.98
$278.00 - $278.00
$278.00
$278.00 - $278.00
$278.00

William Optics Adjustable Flat61 for Z61

WO-P-FLAT61A
1 in stock

1.0x Flattener Power Designed for William Optics Zenithstar 61 Full-Frame Sensor Coverage Adjustable Back Focus Mechanism M54 Telescope Thread &am...

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$278.00 - $278.00
$278.00
$278.00 - $278.00
$278.00
$999.00 - $1,098.00
$999.00 - $1,098.00
$999.00 - $1,098.00
$999.00

William Optics Zenithstar 81 WIFD Telescope

Options available

Patented William Optics Internal Focus Design (WIFD) Rigid M92 Rear Thread with M63 Adapter Included Vixen/Arca-Swiss Dual-Sided Mounting Plate In...

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$999.00 - $1,098.00
$999.00 - $1,098.00
$999.00 - $1,098.00
$999.00
$284.00 - $284.00
$284.00
$284.00 - $284.00
$284.00

William Optics Adjustable Reducer Flattener Flat61R for Z61

WO-P-FLAT61R

Adjustable reducer and field flattener for William Optics Z61 telescope Improves image sharpness and reduces distortion Description ...

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$284.00 - $284.00
$284.00
$284.00 - $284.00
$284.00
$284.00 - $284.00
$284.00
$284.00 - $284.00
$284.00

William Optics Adjustable Reducer Flattener Flat73R for Z73

WO-P-FLAT73R

Reduces focal length by a factor of 0.8x Designed for the William Optics Zenithstar 73 telescope Provides edge-to-edge flat field for full-frame s...

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$284.00 - $284.00
$284.00
$284.00 - $284.00
$284.00