Skip to content

Optical Accessories

Optical accessories are what turn one telescope into several. The same optical tube can be a wide-field imaging refractor, a high-power planetary instrument or a comfortable binocular-view visual scope depending on what you put behind it. David Astro carries a deep selection of eyepieces, diagonals, Barlows, reducers, flatteners, binoviewers and correctors in Canada, held in Canadian stock.

Our team uses this equipment on our own telescopes, so the advice you get is based on what actually works at a given focal ratio and under a given sky, not on a spec sheet. If you are deciding between two focal lengths or wondering whether a corrector will help your optic, ask us before you order.

Filters

SVBONY SV227 H-Alpha 5nm Narrowband Filter - 2"
SVBONY SV227 H-Alpha 5nm Narrowband Filter - 2"
CA$131.00 - CA$131.00
CA$131.00
CA$131.00 - CA$131.00
CA$131.00

SVBONY SV227 H-Alpha 5nm Narrowband Filter - 2"

SV-W9187DB

Isolates the 656.3nm H-Alpha wavelength Aggressive 5nm Full Width at Half Maximum (FWHM) bandpass Peak transmittance of ≥90% for high signal throu...

View full details
CA$131.00 - CA$131.00
CA$131.00
CA$131.00 - CA$131.00
CA$131.00
SVBONY SV227 OIII 5nm Narrowband Filter - 2"
SVBONY SV227 OIII 5nm Narrowband Filter - 2"
CA$131.00 - CA$131.00
CA$131.00
CA$131.00 - CA$131.00
CA$131.00

SVBONY SV227 OIII 5nm Narrowband Filter - 2"

SV-W9187DC

Isolates the Oxygen III emission line at 500.7nm Extremely narrow 5nm Full Width at Half Maximum (FWHM) bandpass Achieves ≥90% peak light transmit...

View full details
CA$131.00 - CA$131.00
CA$131.00
CA$131.00 - CA$131.00
CA$131.00
SVBONY SV227 SHO 5nm H-Alpha OIII SII Narrowband Filter Set - 1.25"
SVBONY SV227 SHO 5nm H-Alpha OIII SII Narrowband Filter Set - 1.25"
CA$235.00 - CA$235.00
CA$235.00
CA$235.00 - CA$235.00
CA$235.00

SVBONY SV227 SHO 5nm H-Alpha OIII SII Narrowband Filter Set - 1.25"

SV-W9187A

Complete 1.25-inch SHO (SII, H-Alpha, OIII) filter set Tight 5nm bandpass for high-contrast imaging Peak transmission rate of ≥90% at key waveleng...

View full details
CA$235.00 - CA$235.00
CA$235.00
CA$235.00 - CA$235.00
CA$235.00
SVBONY SV227 SII 5nm Narrowband Filter - 2"
SVBONY SV227 SII 5nm Narrowband Filter - 2"
CA$131.00 - CA$131.00
CA$131.00
CA$131.00 - CA$131.00
CA$131.00

SVBONY SV227 SII 5nm Narrowband Filter - 2"

SV-W9187DA

Captures Sulfur-II (SII) emission at a 672nm center wavelength Extremely narrow 5nm bandpass for maximum contrast Peak light transmission of ≥90% ...

View full details
CA$131.00 - CA$131.00
CA$131.00
CA$131.00 - CA$131.00
CA$131.00
SVBONY SV230 8-20mm Super Zoom Aspheric Eyepiece - 1.25"
SVBONY SV230 8-20mm Super Zoom Aspheric Eyepiece - 1.25"
CA$420.00 - CA$420.00
CA$420.00
CA$420.00 - CA$420.00
CA$420.00

SVBONY SV230 8-20mm Super Zoom Aspheric Eyepiece - 1.25"

SV-W9185A
1 in stock

8mm to 20mm Continuous Zoom Focal Length Parfocal Design Maintains Focus Across Zoom Range Aspheric Optics for Edge-to-Edge Sharpness Long 17-19mm...

View full details
CA$420.00 - CA$420.00
CA$420.00
CA$420.00 - CA$420.00
CA$420.00
SVBONY SV231 Fringe Killer Color Correction Filter
CA$43.00 - CA$56.00
CA$43.00 - CA$56.00
CA$43.00 - CA$56.00
CA$43.00

SVBONY SV231 Fringe Killer Color Correction Filter

Options available

Reduces violet fringing (chromatic aberration) in achromatic refractors Standard 1.25" filter threads for universal compatibility Blocks IR wavele...

View full details
CA$43.00 - CA$56.00
CA$43.00 - CA$56.00
CA$43.00 - CA$56.00
CA$43.00
Svbony SV233 7 Piece Telescope Accessory Kit
CA$53.00 - CA$53.00
CA$53.00
CA$53.00 - CA$53.00
CA$53.00

SVBONY SV233 7-Piece Telescope Accessory Kit

SV-W9190A
5 in stock

6mm & 17mm Plössl Eyepieces 2x Barlow Lens (2-Element) Moon, ND, and #82A Color Filters 1.25" Barrel Size Fully Multi-Coated Optics M28.5x0.6m...

View full details
CA$53.00 - CA$53.00
CA$53.00
CA$53.00 - CA$53.00
CA$53.00
CA$126.00 - CA$168.00
CA$126.00 - CA$168.00
CA$126.00 - CA$168.00
CA$126.00

SVBONY SV240 Near-Infrared Multi-Narrowband Light Pollution Filter

Options available

Designed for urban astrophotography with one-shot color cameras Passes H-Alpha, OIII, H-Beta, and Near-Infrared (NIR) wavelengths Peak transmittan...

View full details
CA$126.00 - CA$168.00
CA$126.00 - CA$168.00
CA$126.00 - CA$168.00
CA$126.00
SVBONY Zoom Eyepiece SV245
CA$224.00 - CA$224.00
CA$224.00
CA$224.00 - CA$224.00
CA$224.00

SVBONY SV245 Zoom Eyepiece - 1.25"

SV-W9192A

8mm-16mm Zoom Focal Length Parfocal Design Remains in Focus While Zooming Click-Stop Mechanism for Precise Focal Length Selection Comfortable for ...

View full details
CA$224.00 - CA$224.00
CA$224.00
CA$224.00 - CA$224.00
CA$224.00
SVBONY SV260 5-Bandpass Light Pollution Filter - 2"
SVBONY SV260 5-Bandpass Light Pollution Filter - 2"
CA$175.00 - CA$175.00
CA$175.00
CA$175.00 - CA$175.00
CA$175.00

SVBONY SV260 5-Bandpass Light Pollution Filter - 2"

SV-W9194A

5-Bandpass broadband light pollution filter 2-inch size with M48x0.75 thread Over 90% peak transmittance for high signal OD4 blocking of key light...

View full details
CA$175.00 - CA$175.00
CA$175.00
CA$175.00 - CA$175.00
CA$175.00
SVBONY SV520 Astronomy Telescope Complete Kit for Beginners
SVBONY SV520 Astronomy Telescope Complete Kit for Beginners
CA$280.00 - CA$280.00
CA$280.00
CA$280.00 - CA$280.00
CA$280.00

SVBONY SV520 Astronomy Telescope Complete Kit for Beginners

SV-W9302A-W9195A-W9195B

90mm Objective Aperture f/8.9 Focal Ratio Alt-Azimuth Mount with Worm Gear Slow-Motion Controls Includes 3X Barlow Lens 5x24 Optical Finder Scope ...

View full details
CA$280.00 - CA$280.00
CA$280.00
CA$280.00 - CA$280.00
CA$280.00
SVBONY SV905C 1.23MP Type-C Guide Camera - 1.25"
SVBONY SV905C 1.23MP Type-C Guide Camera - 1.25"
CA$154.00 - CA$154.00
CA$154.00
CA$154.00 - CA$154.00
CA$154.00

SVBONY SV905C 1.23MP Type-C Guide Camera - 1.25"

SV-F9198N

1.2MP IMX225 CMOS Sensor 3.75µm Pixel Size Peak Quantum Efficiency: 80% Read Noise: 4.0e Maximum Frame Rate: 39 FPS Back Intercept: 8.5mm / 12.5mm...

View full details
CA$154.00 - CA$154.00
CA$154.00
CA$154.00 - CA$154.00
CA$154.00
SVBONY UHC Light Pollution Filter
CA$34.00 - CA$70.00
CA$34.00 - CA$70.00
CA$34.00 - CA$70.00
CA$34.00

SVBONY UHC Ultra High Contrast Light Pollution Filter

Options available

Reduces light pollution from artificial lighting Enhances contrast for emission nebulae Available in 1.25", 2", and Canon EOS-C formats Durable al...

View full details
CA$34.00 - CA$70.00
CA$34.00 - CA$70.00
CA$34.00 - CA$70.00
CA$34.00
SVBONY UV IR-Cut Telescope Filter
CA$22.00 - CA$25.00
CA$22.00 - CA$25.00
CA$22.00 - CA$25.00
CA$22.00

SVBONY UV IR-Cut Filter

Options available
9 variants in stock

Blocks unwanted Ultraviolet (UV) and Infrared (IR) wavelengths Standard 2-inch filter threads for wide compatibility Improves image contrast and c...

View full details
CA$22.00 - CA$25.00
CA$22.00 - CA$25.00
CA$22.00 - CA$25.00
CA$22.00
Tele Vue 0.8x Focal Reducer 1
CA$564.00 - CA$564.00
CA$564.00
CA$564.00 - CA$564.00
CA$564.00

Tele Vue 0.8x Focal Reducer

TV-TRF-2008

Reduction Factor: 0.8x Optical Design: Reducer and Field Flattener Telescope Connection: 2-inch Barrel Camera Connection: M42x0.75 T-Ring Thread O...

View full details
CA$564.00 - CA$564.00
CA$564.00
CA$564.00 - CA$564.00
CA$564.00
Tele Vue 0.8x Reducer for NP Scopes 2
Tele Vue 0.8x Reducer for NP Scopes 1
CA$801.00 - CA$801.00
CA$801.00
CA$801.00 - CA$801.00
CA$801.00

Tele Vue 0.8x Reducer for NP Scopes

TV-NPR-2073

Focal Length Reduction Factor: 0.8x Optical Design: 4-element, 3-group Telescope Interface: 2.4" Slip-fit Barrel Camera Interface: Threaded for Te...

View full details
CA$801.00 - CA$801.00
CA$801.00
CA$801.00 - CA$801.00
CA$801.00
Tele Vue 0.8x Reducer-Flattener for 102 Scopes 2
Tele Vue 0.8x Reducer-Flattener for 102 Scopes 1
CA$624.00 - CA$624.00
CA$624.00
CA$624.00 - CA$624.00
CA$624.00

Tele Vue 0.8x Reducer-Flattener for 102 Scopes

TV-RFL-4087

Reduction Factor: 0.8x Effective Focal Length (on TV-102): 704mm Effective Focal Ratio (on TV-102): f/6.9 Compatibility: TV-102 and 800-1000mm f...

View full details
CA$624.00 - CA$624.00
CA$624.00
CA$624.00 - CA$624.00
CA$624.00
Tele Vue 2" SCT RichField Kit 1
CA$655.00 - CA$655.00
CA$655.00
CA$655.00 - CA$655.00
CA$655.00

Tele Vue 2" SCT RichField Kit

TV-SCP-8202

SCT Adapter (ACC-0003): threads onto a standard SCT rear cell 2" 90° Everbrite Diagonal (DDP-8004), 99% dielectric mirror 2"-1.25" HiHat adapter i...

View full details
CA$655.00 - CA$655.00
CA$655.00
CA$655.00 - CA$655.00
CA$655.00
Tele Vue 2.5x Powermate - 1.25" 2
Tele Vue 2.5x Powermate - 1.25" 1
CA$364.00 - CA$364.00
CA$364.00
CA$364.00 - CA$364.00
CA$364.00

Tele Vue 2.5x Powermate - 1.25"

TV-PMT-2513

Magnification: 2.5x Barrel Size: 1.25" Optical Design: 4-Element Pupillary Corrector Compatibility: Visual and Photographic Use Filter Threads: Ye...

View full details
CA$364.00 - CA$364.00
CA$364.00
CA$364.00 - CA$364.00
CA$364.00
Tele Vue 2x Barlow - 1.25" 2
Tele Vue 2x Barlow - 1.25" 1
CA$214.00 - CA$214.00
CA$214.00
CA$214.00 - CA$214.00
CA$214.00

Tele Vue 2x Barlow - 1.25"

TV-BLW-2125
1 in stock

Magnification Factor: 2x Barrel Size: 1.25" Optical Design: 2-Element, Fully Multi-Coated Eyepiece Holder: Brass Compression Ring Filter Threads: ...

View full details
CA$214.00 - CA$214.00
CA$214.00
CA$214.00 - CA$214.00
CA$214.00
Tele Vue 2x BIG Barlow - 2" 2
Tele Vue 2x BIG Barlow - 2" 1
CA$364.00 - CA$364.00
CA$364.00
CA$364.00 - CA$364.00
CA$364.00

Tele Vue 2x BIG Barlow - 2"

TV-BWC-2211
1 in stock

Magnification Factor: 2x Barrel Size: 2" with 1.25" Adapter Optical Design: 4-Element, Telecentric Coatings: Fully Multi-Coated Filter Threads: Ye...

View full details
CA$364.00 - CA$364.00
CA$364.00
CA$364.00 - CA$364.00
CA$364.00
Tele Vue 2x Powermate - 2" 2
Tele Vue 2x Powermate - 2" 1
CA$543.00 - CA$543.00
CA$543.00
CA$543.00 - CA$543.00
CA$543.00

Tele Vue 2x Powermate - 2"

TV-PMT-2200
2 in stock

Magnification Factor: 2x Barrel Size: 2" Optical Design: 4-element Telecentric Amplifier Coatings: Fully Multi-Coated Filter Threads: Yes (48mm / ...

View full details
CA$543.00 - CA$543.00
CA$543.00
CA$543.00 - CA$543.00
CA$543.00
Tele Vue 3x Barlow - 1.25" 2
Tele Vue 3x Barlow - 1.25" 1
CA$214.00 - CA$214.00
CA$214.00
CA$214.00 - CA$214.00
CA$214.00

Tele Vue 3x Barlow - 1.25"

TV-BLW-3125
1 in stock

Magnification Factor: 3x Barrel Size: 1.25" Optical Design: 3-element, apochromatic Coatings: Fully multi-coated Compression Ring: Yes, brass Filt...

View full details
CA$214.00 - CA$214.00
CA$214.00
CA$214.00 - CA$214.00
CA$214.00
Tele Vue 4x Powermate - 2" 2
Tele Vue 4x Powermate - 2" 1
CA$554.00 - CA$554.00
CA$554.00
CA$554.00 - CA$554.00
CA$554.00

Tele Vue 4x Powermate - 2"

TV-PMT-4201
1 in stock

Magnification Factor: 4x Barrel Size: 2" Optical Design: 4-Element Pupillary Corrector Compatibility: 2" and 1.25" Eyepieces (with adapter) Primar...

View full details
CA$554.00 - CA$554.00
CA$554.00
CA$554.00 - CA$554.00
CA$554.00

Choosing Optical Accessories That Match Your Telescope

Every accessory in this collection modifies the light cone before it reaches your eye or sensor. The right choice depends almost entirely on your telescope's focal ratio, focal length and back-focus budget.

  • Eyepieces: Focal length sets magnification against your telescope's focal length; apparent field and eye relief determine how comfortable that magnification is to use.
  • Diagonals: Dielectric mirrors typically exceed 99% reflectivity; prisms can outperform them at f/10 and slower on planetary targets but introduce chromatic effects in fast refractors.
  • Barlow lenses and extenders: Multiply focal length for planetary work and push the focal plane outward, which is often the cheapest fix for a scope that will not reach focus with a diagonal.
  • Field flatteners and reducers: Correct field curvature and coma across large sensors; each has a fixed back-focus that must be hit precisely.
  • Binoviewers: Two-eye viewing that dramatically improves perceived detail on the Moon and planets, at the cost of significant added optical path.
  • Finders and reflex sights: Acquisition optics — the accessory most often skipped and most often missed.

Why Choose David Astro for Optical Accessories

Optics are easy to buy badly. A well-reviewed eyepiece can still be the wrong eyepiece for your focal ratio, exit pupil or sky.

  • Focal length guidance: We help you build a spaced eyepiece set rather than three focal lengths that overlap, and we calculate exit pupil against your aperture and typical seeing.
  • Corrector matching: We confirm that a flattener or reducer is designed for your telescope's focal ratio before you buy, since a mismatched corrector degrades a field rather than fixing it.
  • Authorized dealer: Full manufacturer warranty and verified authenticity on everything we list.
  • Canadian stock: In-stock optics ship from Canada, with no surprise duties or brokerage fees for Canadian customers.
  • Service and support after the sale: In-house diagnostics if something is not performing as expected.

Optical Accessories in Canada — Frequently Asked Questions

Will a premium eyepiece improve a modest telescope?
Usually yes at the edges of the field, especially in fast telescopes below f/6 where simpler designs struggle. On the axis at f/10, the difference between a good eyepiece and a premium one is much smaller.
How do I know if I need a flattener or a reducer?
A flattener corrects curvature at the same focal length. A reducer also shortens focal length, widening the field and speeding the system. If your stars are elongated only in the corners, you need a flattener; if you also want more field, a reducer.
Do binoviewers work in every telescope?
They add roughly 100 mm or more of optical path, so most refractors need a corrector or a Barlow-style element to reach focus. Schmidt-Cassegrains generally accommodate them without modification.
Is everything shipped domestically?
Yes. Anything shown as in stock is held in Canada and ships without customs delays for Canadian orders.

Match the accessory to the optic

Tell us your telescope and what you want to see, and we will recommend the right combination. Ships from Canada.