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Adapters

Almost every imaging train problem in astrophotography — soft corners, elongated stars, a camera that will not come to focus — traces back to a few millimetres of the wrong adapter. David Astro carries adapters in Canada covering M42, M48, M54, M68, SCT and Nikon and Canon bayonet standards, along with barrel adapters in 1.25" and 2", all in stock and shipping from Canada.

Adapters are the one product category where buying blind is genuinely expensive. Our team calculates back-focus and thread compatibility for customers every day, so before you assemble a stack from guesswork, send us your components and we will specify the parts.

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Baader Planetarium Adapter 3.3"i to M68i – for Celestron / Astro Physics
CA$194.00 - CA$194.00
CA$194.00
CA$194.00 - CA$194.00
CA$194.00

Baader Planetarium Adapter 3.3"i to M68i – for Celestron / Astro Physics

BAA-2458217

Connects 3.3" telescope threads to the M68i accessory system Designed for Celestron EdgeHD 9.25", 11", and 14" models Compatible with Celestron SC...

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CA$194.00 - CA$194.00
CA$194.00
CA$194.00 - CA$194.00
CA$194.00
Baader Planetarium Adapter 4.1"i to M68i – for TEC 140-200 and 3.5" Feathertouch focuser
CA$225.00 - CA$225.00
CA$225.00
CA$225.00 - CA$225.00
CA$225.00

Baader Planetarium Adapter 4.1"i to M68i – for TEC 140-200 and 3.5" Feathertouch focuser

BAA-2458191

Connects 4.1" TEC and 3.5" Feathertouch focusers to the Baader M68 system Creates a rigid, all-threaded connection for maximum stability Engineere...

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CA$225.00 - CA$225.00
CA$225.00
CA$225.00 - CA$225.00
CA$225.00
Baader Planetarium Adapter 6x7 Flange to M68i – for TEC/AP Field Flattener
CA$225.00 - CA$225.00
CA$225.00
CA$225.00 - CA$225.00
CA$225.00

Baader Planetarium Adapter 6x7 Flange to M68i – for TEC/AP Field Flattener

BAA-2458245

Adapts 6x7 Flange to M68i Female Thread Compatible with select Astro-Physics Field Flatteners Compatible with select TEC Field Flatteners Enables ...

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CA$225.00 - CA$225.00
CA$225.00
CA$225.00 - CA$225.00
CA$225.00
Baader Planetarium Adapter D60 (Pentax) to 2" Nosepiece
CA$54.00 - CA$54.00
CA$54.00
CA$54.00 - CA$54.00
CA$54.00

Baader Planetarium Adapter D60 (Pentax) to 2" Nosepiece

BAA-6015180

Adapts female Pentax D60 threads to a male 2" nosepiece Enables the use of standard 2" diagonals, eyepieces, and camera adapters Provides a secure...

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CA$54.00 - CA$54.00
CA$54.00
CA$54.00 - CA$54.00
CA$54.00
Baader Planetarium Adapter M48a to T-2a
CA$44.00 - CA$44.00
CA$44.00
CA$44.00 - CA$44.00
CA$44.00

Baader Planetarium Adapter M48a to T-2a

BAA-2958554
2 in stock

Connects M48 Female and T-2 Female Threaded Components M48 Male (External) Thread on One Side T-2 Male (External) Thread on the Other Side Solves ...

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CA$44.00 - CA$44.00
CA$44.00
CA$44.00 - CA$44.00
CA$44.00
Baader Planetarium Adapter M48i to T-2a
CA$44.00 - CA$44.00
CA$44.00
CA$44.00 - CA$44.00
CA$44.00

Baader Planetarium Adapter M48i to T-2a

BAA-2958556
1 in stock

Connects M48 Female Threads to T-2 Male Threads Part of the Baader Astro T-2 System Low-Profile Design Minimizes Optical Path Length Precision Mac...

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CA$44.00 - CA$44.00
CA$44.00
CA$44.00 - CA$44.00
CA$44.00
Baader Planetarium Adapter M54a to M48i
CA$53.00 - CA$53.00
CA$53.00
CA$53.00 - CA$53.00
CA$53.00

Baader Planetarium Adapter M54a to M48i

BAA-2958751
1 in stock

Connects M54 Male Threads to M48 Female Threads Enables Use of Standard 2-inch (M48) Filters Low-Profile Design Minimizes Back Focus Consumption P...

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CA$53.00 - CA$53.00
CA$53.00
CA$53.00 - CA$53.00
CA$53.00
Baader Planetarium Adapter M54i to S52a – for Wide-T-Rings
CA$53.00 - CA$53.00
CA$53.00
CA$53.00 - CA$53.00
CA$53.00

Baader Planetarium Adapter M54i to S52a – for Wide-T-Rings

BAA-2958754

Adapts Baader S52 Wide T-Rings to M54 male threads Provides a secure, threaded connection to prevent camera tilt Maintains maximum clear aperture ...

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CA$53.00 - CA$53.00
CA$53.00
CA$53.00 - CA$53.00
CA$53.00
Baader Planetarium Adapter M54i to T-2a
CA$53.00 - CA$53.00
CA$53.00
CA$53.00 - CA$53.00
CA$53.00

Baader Planetarium Adapter M54i to T-2a

BAA-2958753
1 in stock

Connects M54 (female) threaded components to T-2 (male) accessories Enables integration of T-2 filter wheels, guiders, and cameras Creates a secur...

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CA$53.00 - CA$53.00
CA$53.00
CA$53.00 - CA$53.00
CA$53.00
Baader Planetarium Adapter M55a to M68i
CA$69.00 - CA$69.00
CA$69.00
CA$69.00 - CA$69.00
CA$69.00

Baader Planetarium Adapter M55a to M68i

BAA-2458234

Adapts M55 External (M55a) Threads Provides a Secure M68 Internal (M68i) Thread Enables Connection to the Baader M68 System Designed for Specific ...

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CA$69.00 - CA$69.00
CA$69.00
CA$69.00 - CA$69.00
CA$69.00
Baader Planetarium Adapter M68a to M48a
CA$75.00 - CA$75.00
CA$75.00
CA$75.00 - CA$75.00
CA$75.00

Baader Planetarium Adapter M68a to M48a

BAA-2458229

Converts M68 Internal Threads to M48 External Threads Provides a Standard Male M68 to Male M48 Connection Enables Attaching 2-inch (M48) Accessori...

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CA$75.00 - CA$75.00
CA$75.00
CA$75.00 - CA$75.00
CA$75.00
Baader Planetarium Adapter M68a to M54a
CA$78.00 - CA$78.00
CA$78.00
CA$78.00 - CA$78.00
CA$78.00

Baader Planetarium Adapter M68a to M54a

BAA-2458230

Connects M68 Male Threads to M54 Male Threads Functions as a Reducer for Optical Trains Precision-Machined for Secure, No-Flexure Connections Blac...

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CA$78.00 - CA$78.00
CA$78.00
CA$78.00 - CA$78.00
CA$78.00
Baader Planetarium Adapter M68a to M62a
CA$81.00 - CA$81.00
CA$81.00
CA$81.00 - CA$81.00
CA$81.00

Baader Planetarium Adapter M68a to M62a

BAA-2458228

Adapts M68 Male (External) Threads to M62 Male (External) Threads Provides a Secure, Rigid Connection Between Components CNC-Machined for Precise ...

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CA$81.00 - CA$81.00
CA$81.00
CA$81.00 - CA$81.00
CA$81.00
Baader Planetarium Adapter M68a to SP54a – Hyperion® DT-Ring
CA$70.00 - CA$70.00
CA$70.00
CA$70.00 - CA$70.00
CA$70.00

Baader Planetarium Adapter M68a to SP54a – Hyperion® DT-Ring

BAA-2458060

Adapts M68a (External) Threads to SP54a (External) Threads Engineered for Baader FFC and Telecentric Systems Provides the Shortest Possible Mechan...

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CA$70.00 - CA$70.00
CA$70.00
CA$70.00 - CA$70.00
CA$70.00
Baader Planetarium Adapter M82a to M68i
CA$75.00 - CA$75.00
CA$75.00
CA$75.00 - CA$75.00
CA$75.00

Baader Planetarium Adapter M82a to M68i

BAA-2458198

Adapts M82x1 female threads to M68x1 female threads Enables a rigid, direct-threaded connection to your focuser Designed for the Baader M68 system...

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CA$75.00 - CA$75.00
CA$75.00
CA$75.00 - CA$75.00
CA$75.00
Baader Planetarium Adapter M86i to M68i – for TEC 110FL
CA$209.00 - CA$209.00
CA$209.00
CA$209.00 - CA$209.00
CA$209.00

Baader Planetarium Adapter M86i to M68i – for TEC 110FL

BAA-2458192

Connects the TEC 110FL focuser's M86i thread to the Baader M68i system Provides a rigid, zero-flexure connection for astrophotography Enables secu...

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CA$209.00 - CA$209.00
CA$209.00
CA$209.00 - CA$209.00
CA$209.00
Baader Planetarium Adapter S65a to M68a
CA$85.00 - CA$85.00
CA$85.00
CA$85.00 - CA$85.00
CA$85.00

Baader Planetarium Adapter S65a to M68a

BAA-2458215

Connects S65a Threaded Accessories to M68a Ports Designed for Baader #24580-35 & #24580-36 DSLR T-Rings Enables Use of T-Rings with a 2-Filter...

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CA$85.00 - CA$85.00
CA$85.00
CA$85.00 - CA$85.00
CA$85.00
Baader Planetarium Alan Gee Mark II Centering Ring for SC 9¼"
CA$40.00 - CA$40.00
CA$40.00
CA$40.00 - CA$40.00
CA$40.00

Baader Planetarium Alan Gee Mark II Centering Ring for SC 9.25"

BAA-2454410

Adapts Alan Gee II Telecompressor to larger SCTs Ensures precise optical alignment Designed for Celestron 9.25" and 11" Schmidt-Cassegrain OTAs Pr...

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CA$40.00 - CA$40.00
CA$40.00
CA$40.00 - CA$40.00
CA$40.00
Baader Planetarium IMP85 Adapter S120a to FT3.5"
CA$363.00 - CA$363.00
CA$363.00
CA$363.00 - CA$363.00
CA$363.00

Baader Planetarium IMP85 Adapter S120a to FT3.5"

BAA-2451314

Three-Port Electronic Instrument Selector Unmirrored, Zero Light-Loss Main Imaging Port (Port 1) Two Mirrored Ports for Ancillary Instruments (Por...

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CA$363.00 - CA$363.00
CA$363.00
CA$363.00 - CA$363.00
CA$363.00
Baader Planetarium IMP85 Adapter S120a to Hedrick Focuser
CA$286.00 - CA$286.00
CA$286.00
CA$286.00 - CA$286.00
CA$286.00

Baader Planetarium IMP85 Adapter S120a to Hedrick Focuser

BAA-2451310

Connects IMP85 Instrument Selector to 3.5" Hedrick Focuser Compatible with PlaneWave CDK 14/17/20/24 Telescopes Enables Remote, Electronic Switchi...

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CA$286.00 - CA$286.00
CA$286.00
CA$286.00 - CA$286.00
CA$286.00
Baader Planetarium IMP85 Adapter S120a to IR90 Focuser
CA$695.00 - CA$695.00
CA$695.00
CA$695.00 - CA$695.00
CA$695.00

Baader Planetarium IMP85 Adapter S120a to IR90 Focuser

BAA-2451311

Connects IMP85 Instrument Selector to IR90 Focusers Enables Multi-Instrument Setups Facilitates Remote Observatory Automation Solid, Precision-Mac...

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CA$695.00 - CA$695.00
CA$695.00
CA$695.00 - CA$695.00
CA$695.00
Baader Planetarium IMP85 Adapter S120a to IR90 Focuser Short (20mm)
CA$270.00 - CA$270.00
CA$270.00
CA$270.00 - CA$270.00
CA$270.00

Baader Planetarium IMP85 Adapter S120a to IR90 Focuser Short (20mm)

BAA-2451316

Adapts the IMP85 instrument selector to telescopes with an IR90 focuser Provides a short, rigid connection with a 20mm optical path length Enables...

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CA$270.00 - CA$270.00
CA$270.00
CA$270.00 - CA$270.00
CA$270.00
Baader Planetarium IMP85 Adapter S120a to M100a
CA$302.00 - CA$302.00
CA$302.00
CA$302.00 - CA$302.00
CA$302.00

Baader Planetarium IMP85 Adapter S120a to M100a

BAA-2451312

Adapts the IMP85 Instrument Selector S120a Port Connects to M100a Male Threads Enables Multi-Port Instrument Configurations Provides a Solid, Secu...

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CA$302.00 - CA$302.00
CA$302.00
CA$302.00 - CA$302.00
CA$302.00
Baader Planetarium IMP85 Adapter S120a to M100i
CA$302.00 - CA$302.00
CA$302.00
CA$302.00 - CA$302.00
CA$302.00

Baader Planetarium IMP85 Adapter S120a to M100i

BAA-2451313

Connects IMP85 Port Selector to M100i threaded accessories Telescope-Side Thread: S120a Camera-Side Thread: M100i (M100x1 female) Designed for All...

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CA$302.00 - CA$302.00
CA$302.00
CA$302.00 - CA$302.00
CA$302.00

Understanding Thread Standards and Back-Focus

An adapter does two things at once: it changes the connection type, and it changes the distance between your corrector and your sensor. The second effect is the one that causes trouble, because most reducers and flatteners have a back-focus tolerance of about one millimetre.

  • M42 (T-thread, 0.75 mm pitch): The long-standing standard for camera adapters. Its clear aperture will vignette sensors larger than APS-C, so full-frame imaging trains should avoid it.
  • M48 (2" thread, 0.75 mm pitch): The practical choice for APS-C and full-frame sensors, with enough clear aperture to avoid mechanical vignetting.
  • M54 and M68: Larger-diameter threads used by heavier astrographs and larger-format correctors where rigidity and aperture both matter.
  • SCT 2"-24 TPI: The rear-cell thread on Schmidt-Cassegrains; requires a specific adapter to reach M42 or M48 for imaging.
  • Bayonet adapters: Canon EF and Nikon F adapters place a DSLR or mirrorless body at the correct flange distance, typically 44 mm and 46.5 mm respectively.
  • Fine-tuning spacers: 0.5 mm, 1 mm and 2 mm shims that let you land exactly on a corrector's specified spacing rather than near it.

Why Choose David Astro for Adapters

An adapter is a cheap part that determines whether an expensive telescope performs. We treat it that way.

  • Free back-focus calculation: Give us your camera, filter thickness, reducer and telescope and we will return a component list with the total spacing worked out.
  • Filter thickness accounted for: Glass in the light path shifts focus by roughly one third of its thickness, and we include that in the calculation rather than leaving you to discover it.
  • Male and female threads identified: We specify the gender and standard on both ends, which is the detail most listings omit.
  • Deep Canadian stock: Hundreds of adapters held domestically, so a missing 10 mm spacer does not cost you three weeks of clear sky.
  • Authorized dealer: Genuine manufacturer parts with full warranty, shipped from Canada without duties for Canadian buyers.

Adapters in Canada — Frequently Asked Questions

How do I calculate my back-focus?
Add your camera's sensor-to-flange distance, any filter wheel or off-axis guider, the filter's optical shift, and every spacer between the camera and the corrector. That total must match the corrector's specified figure, usually 55 mm for a standard reducer.
Should I use M42 or M48?
Use M48 for any sensor larger than APS-C. M42 has enough clear aperture for smaller sensors but will mechanically vignette a full-frame chip regardless of the optics ahead of it.
Do filters change my spacing?
Yes. A filter shifts the focal plane by about one third of its glass thickness. A 3 mm filter adds roughly 1 mm to the effective optical path, which is enough to matter at a 55 mm target.
What if I order the wrong adapter?
Contact us with your setup before ordering and we will confirm the parts. That is a faster path than exchanges, and it is a service we provide free.

Send us your imaging train

We will calculate the spacing and specify every adapter you need. Canadian stock, no guesswork.