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William Optics

William Optics

(80 products)

William Optics Telescopes & Accessories

William Optics designs premium refractor telescopes and astrophotography accessories, including the renowned RedCat series of compact Petzval astrographs. Known for elegant design, excellent color correction, and flat-field performance, William Optics products are trusted by astrophotographers and visual observers alike.

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William Optics
William Optics Longer Adjusting Adapter for FLAT68III, FLAT7A (AD-M80-45-M48)

Sale price $76⁰⁰ Regular price $80⁰⁰

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$8.00 off

William Optics
William Optics 90° 1.25" Erect Prism (D-EP90-125II)

(1)

Sale price $152⁰⁰ Regular price $160⁰⁰

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$24.00 off

William Optics
William Optics 0.8x Flattener/Reducer for Fluorostar 91 (P-FLAT6AIII-M92)

(1)

Sale price $456⁰⁰ Regular price $480⁰⁰

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$181.85 off

William Optics
William Optics Mighty-Cat 71 · 30th Anniversary Limited Edition (T-MC-71RD-30A)

(1)

Sale price $3,455¹⁵ Regular price $3,637⁰⁰

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William Optics
William Optics ZWO EAF Mounting Bracket for WIFD System

Sale price $259³⁵ Regular price $273⁰⁰

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William Optics
William Optics Ultra-Cat 56 (T-C-56BR)

Sale price $1,383⁰⁰ Regular price $1,929⁰⁰

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$242.64 off

William Optics
William Optics WIFD Ultra-Cat 76 f/4.8 APO (T-C-76)

Sale price $2,790³⁶ Regular price $3,033⁰⁰

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$6.75 off

William Optics
William Optics SCT to 1.25" RotoLock Visual Back Adapter (F-ROTO-A2-125-SCT-TA)

Sale price $128²⁵ Regular price $135⁰⁰

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$75.05 off

William Optics
William Optics Spacecat 51 WIFD (L-RC51SGIII)

Sale price $1,425⁹⁵ Regular price $1,501⁰⁰

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William Optics
William Optics ZenithStar 81 Doublet WIFD APO f/6.9

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Sale price $1,439²⁵ Regular price $1,515⁰⁰

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William Optics
William Optics Micro 4/3 48mm T mount for Olympus - Space Gray (TM-MFT-M48)

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Sale price $72²⁰ Regular price $76⁰⁰

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$William Optics Fluorostar 91 f/5.9 Triplet Refractor (FLT-91) - Astronomy Plus$ $William Optics Fluorostar 91 f/5.9 Triplet Refractor (FLT-91) - Astronomy Plus$
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William Optics
William Optics Fluorostar 91 f/5.9 Triplet Refractor (FLT-91)

Sale price $2,881³⁵ Regular price $3,033⁰⁰

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$54.35 off

William Optics
William Optics Flattener FLAT68III (P-FLAT68III)

Sale price $1,032⁶⁵ Regular price $1,087⁰⁰

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$2.70 off

William Optics
William Optics Extension Bar For iOptron Skyguider Pro (M-IO-EB20RD)

Sale price $51³⁰ Regular price $54⁰⁰

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William Optics
William Optics 48mm T mount for Nikon Z Mirrorless Camera (TM-NK-Z-M48)

Sale price $89³⁰ Regular price $94⁰⁰

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Since 1988, Astronomy Plus has been a trusted Canadian source for telescopes, astrophotography equipment, and optics. We provide expert advice, quality products, and fast shipping across Canada.

📍3008 Brodeur West , Unit 307
St-Alphonse-de-Granby, Quebec, Canada
J0E 2A0

📞 450-463-5072 / 1-888-540-0444

✉️ info@astronomyplus.com

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★ Reviews

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1918 reviews

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1151

Celestron SkySync GPS Accessory (93969)

Robert Larose

GPS simplifie la vie

Fonctionne immédiatement une fois qu’on sait qu’il faut activer avec la manette. À date aucun délai au démarrage sur plusieurs sessions.

ZWO ASI585MC USB3.0 Color Astronomy Camera - OPEN BOX (ASI585MC)

Yosmany Castaneda

Excellent camera for "Lucky imaging" of planets

Excellent camera for "Lucky imaging" of planets.

Celestron StarSense Explorer DX 102AZ Refractor (22460)

Alexandre Cyr

Très satisfait

Très bon outils pour amateur. Explication clair et rapide à monter. Personnel très sympathique aussi :-)

ZWO Seestar S50 Pro All-in-One APO Smart Telescope (S50PRO)

Bluespeck

Excellent service

Excellent service. Excellent product. Thanks Astronomy Plus!!

Astrozap Dust Covers for Telescopes, Dew Shields, Finders, Eyepieces and Binoculars

DVB

Clever tube end covers for my non-standard home-built 10" Newtonian

Clever tube end covers for my non-standard home-built 10" Newtonian. Kind of like shower caps, but they are of heavy-duty material. I haven't yet tested them to see if they will keep out enough light to shoot dark flats, but I think they will be.

Yosmany Castaneda

Excellent camera for "Lucky imaging" of planets

Excellent camera for "Lucky imaging" of planets.

ZWO ASI585MC USB3.0 Color Astronomy Camera - OPEN BOX (ASI585MC)

David W Vandenberg

Excellent Service

Products as described, arrived 3 days before due date.
This is a great deep sky scope, and I am looking forward to getting some great pictures with it, all I need now are some clear skies (it's raining at the moment)

SVBONY SV545 Petzval Astrograph 203mm Lens F/4.5 (W9317B)

Emilio Youssef

Very sturdy and better than

Very sturdy and better than expected!

Astronomy Plus Pier Extension for ZWO, iOptron and Sky-Watcher Mounts

Claude Lamarre

ASTRONOMIK MC CLEAR FILTER 2’’ SCT 24 TPI Se visse directement sur l’adaptateur 2’’ SCT 24 TPI

ASTRONOMIK MC CLEAR FILTER 2’’ SCT 24 TPI

Se visse directement sur l’adaptateur 2’’ SCT 24 TPI , votre dos visuel se visse sur le ASTRONOMIK MC CLEAR FILTER 2’’ SCT 24 TPI.

1) Permet de sceller le tube optique. Une touche de graisse de silicone pure, de qualité, celle pour les équipements de plongée assure l’étanchéité.

2) Empêche les contaminants de s’infiltrer

3) Empêche l’effet cheminée lorsqu’on change un oculaire ou un accessoire par temps froids.

4) Combiné à une isolation thermique de l'OTA un isolant thermique à double face genre REFLECTIX, permet de sortir l’instrument d’un local chauffé vers la température frigide extérieure pour observer immédiatement sans attendre l’équilibrage des températures.

J’ai testé de 25C à 5C, sur deux nuits à l’oculaire clavé 10mm dès l’installation 5 minutes après la sortie de l’instrument, l’image est absolument nette avec seulement la turbulence d’un seeing de 3-4, et ce durant toute la durée de la séance.

Images de Saturne au MK127 de SVBONY F:1500mm, Caméra ZWO ASI 678MC au foyer primaire, Filtre 1.25" Baader contrast boost, capture .SER, Sharpcap, PIPP, AS4!, registax 6.

Les photos sont un stack des images brutes stabilisé de PIPP, et l'autre un léger traitement dans Registax 6.

Le 27 octobre vers 21h30 5 à 10 minutes après avoir sorti l’instrument, viewing 3/5. Hier avec barlow QT 2,25x Baader, résultat similaire. C'est ce que j'espérait, les tests se poursuivre.

Astronomik MC-clear Filter

Darus

Helpful staff and competitive pricing make them a solid choice

Astronomy Plus is a reliable Canadian retailer specializing in telescopes and astrophotography gear.

Their product selection is excellent — everything from smart telescopes like the Seestar series to mounts, cameras, filters, and accessories from top brands. Items arrive in perfect condition and are well-stocked.

Shipping is impressively fast!

Astronomy Plus – Telescopes & Astrophotography Canada