Réflecteurs
No design delivers more aperture for the money than a Newtonian reflector. A mirror is cheaper to make well than a lens, has no chromatic aberration whatsoever, and scales to sizes that would be impossible in glass — which is why almost every large amateur telescope is a reflector. David Astro carries reflectors in Canada, from fast imaging astrographs to large visual Newtonians, stocked in Canada and shipped worldwide.
The trade is collimation and a coma corrector. Both are manageable, and we will be straightforward about what each telescope actually needs.
Filtres
Orion Optics UK AG8 f/3.8 Astrograph OTA
200mm (8-inch) Primary Mirror 760mm Focal Length Extremely Fast f/3.8 Focal Ratio 45mm Corrected Flat Field Circle Carbon Fibre Sandwich Tube Cons...
Afficher tous les détailsOrion Optics UK CT10 Optical Tube Assembly
250mm (10") Aperture Newtonian Reflector 1200mm Focal Length f/4.8 Focal Ratio Guaranteed 1/10 PV Wavefront Optics Carbon Fibre Sandwich Construct...
Afficher tous les détailsOrion Optics UK CT10L Optical Tube Assembly
250mm (10-inch) Aperture 1575mm Focal Length (f/6.3) Guaranteed 1/10 PV Wavefront Optics Carbon Fibre Sandwich Tube Construction 12.5kg Optical Tu...
Afficher tous les détailsOrion Optics UK CT12 Optical Tube Assembly
300mm (12") Aperture f/4 Newtonian Reflector 1200mm Focal Length Certified 1/10 PV Wavefront Primary Mirror Carbon Fiber Sandwich Tube Constructio...
Afficher tous les détailsOrion Optics UK CT12L Optical Tube Assembly
300mm (12") Aperture 1590mm Focal Length, f/5.3 Focal Ratio Standard 1/10 PV Wavefront Optics Carbon Fibre Sandwich Tube Construction 2" Focuser w...
Afficher tous les détailsOrion Optics UK CT14 Optical Tube Assembly
350mm (14") Aperture 1600mm Focal Length (f/4.6) Guaranteed 1/10 PV Wavefront Optics Carbon Fibre Sandwich Tube Construction 26kg Optical Tube Wei...
Afficher tous les détailsOrion Optics UK CT16 Optical Tube Assembly
400mm (16") Aperture 1600mm Focal Length (f/4) 1/10 PV Wavefront Standard Optics Carbon Fiber Sandwich Tube Construction 36kg Optical Tube Weight ...
Afficher tous les détailsOrion Optics UK CT8 Optical Tube Assembly
200mm (8") Aperture 900mm Focal Length (f/4.5) 1/10 PV Wavefront Certified Optics Carbon Fiber Sandwich Tube Construction 7kg Optical Tube Weight ...
Afficher tous les détailsOrion Optics UK IDEAL 10 Optical Tube Assembly
250mm (10-inch) Primary Mirror 1200mm Focal Length f/4.8 Focal Ratio Standard 1/6 PV Wavefront Hand-Figured Optics 11kg Nominal Tube Weight Des...
Afficher tous les détailsOrion Optics UK IDEAL 10L Optical Tube Assembly
250mm (10-inch) primary mirror diameter 1600mm focal length (f/6.3) Standard 1/6 PV wavefront optical accuracy CNC-machined 9-point suspension mir...
Afficher tous les détailsOrion Optics UK IDEAL 12 Optical Tube Assembly
300mm (12") Primary Mirror 1200mm Focal Length f/4 Focal Ratio 1/6 PV Wavefront Standard Optics 14kg Tube Weight Description FAQ Specifications...
Afficher tous les détailsOrion Optics UK IDEAL 12L Optical Tube Assembly
300mm (12") Primary Mirror Diameter 1600mm Focal Length (f/5.3) 1/6 PV Wavefront Standard Optical Accuracy Eris 2" Rack and Pinion Focuser 16kg No...
Afficher tous les détailsOrion Optics UK IDEAL 14 Optical Tube Assembly
350mm (14") Primary Mirror 1600mm Focal Length (f/4.6) Standard 1/6 PV Wavefront Hand-Figured Optics CNC-Machined 9-Point Suspension Mirror Cell E...
Afficher tous les détailsOrion Optics UK IDEAL 16 Optical Tube Assembly
400mm (16") Primary Mirror 1600mm Focal Length Fast f/4 Focal Ratio Standard 1/6 PV Wavefront Optics with Zygo Report CNC-Machined 9-Point Mirror ...
Afficher tous les détailsOrion Optics UK IDEAL 6 Optical Tube Assembly
150mm (6") Primary Mirror 750mm Focal Length (f/5) Standard 1/6 PV Wavefront Hand-Figured Optics Lightweight 4.5kg Aluminium Tube Eris 2" Rack &am...
Afficher tous les détailsOrion Optics UK IDEAL 6L Optical Tube Assembly
150mm (6") Newtonian Reflector Optical Tube 1200mm Focal Length at an f/8 Focal Ratio Certified 1/6 PV Wavefront Primary Mirror Optics CNC-Machine...
Afficher tous les détailsOrion Optics UK IDEAL 8 Optical Tube Assembly
200mm (8") Primary Mirror 900mm Focal Length Fast f/4.5 Focal Ratio Guaranteed 1/6 PV Wavefront Standard Optics CNC-Machined 9-Point Mirror Cell 7...
Afficher tous les détailsOrion Optics UK IDEAL 8L Optical Tube Assembly
200mm Primary Mirror 1200mm Focal Length (f/6) 1/6 PV Wavefront Standard Optics CNC 9-Point Suspension Mirror Cell Eris 2" Rack and Pinion Focuser...
Afficher tous les détailsOrion Optics UK ODK10 Optical Tube Assembly
250mm (10") Corrected Dall-Kirkham Optics 1700mm Focal Length at f/6.8 50mm Fully Corrected Flat Image Circle 3.5μm On-Axis Spot Size Carbon Fibre...
Afficher tous les détailsOrion Optics UK ODK10Tr Truss Optical Tube Assembly
250mm (10-inch) Optimized Dall-Kirkham optics 1700mm focal length at a native f/6.8 focal ratio 50mm fully corrected, flat image circle for large ...
Afficher tous les détailsOrion Optics UK ODK12 Optical Tube Assembly
300mm (12") Optimised Dall-Kirkham Optics 2040mm Focal Length at a fast f/6.8 Focal Ratio Covers a greater than 52mm flat imaging circle Delivers ...
Afficher tous les détailsOrion Optics UK ODK12Tr Truss Optical Tube Assembly
300mm (12") Optimized Dall-Kirkham Astrograph 2040mm Focal Length (f/6.8) >52mm Flat, Corrected Image Circle 1.8µm On-Axis Spot Size Carbon Fib...
Afficher tous les détailsOrion Optics UK ODK14 Optical Tube Assembly
Primary Mirror Diameter: 350mm Focal Ratio: f/6.8 Corrected Image Circle: >52mm Tube Material: Carbon Fibre Sandwich Back Focus: 210mm Tu...
Afficher tous les détailsOrion Optics UK ODK14Tr Truss Optical Tube Assembly
350mm (14") Optimized Dall-Kirkham Optics 2380mm Focal Length (f/6.8) >52mm Fully Illuminated and Corrected Image Circle 2.1µm On-Axis Spot Siz...
Afficher tous les détailsNewtonian Design and What It Demands
A parabolic primary and a flat diagonal secondary. Simple, efficient, and with two characteristics you have to work with rather than around.
- Focal ratio and its consequences: Fast Newtonians around f/4 give wide bright fields for imaging but demand precise collimation and a coma corrector. Slower f/6 to f/8 designs are far more forgiving.
- Coma: Off-axis stars take a comet shape, inherent to a parabolic mirror and increasingly obvious as focal ratio drops. A coma corrector is effectively mandatory below f/6 for imaging.
- Collimation: Mirror alignment shifts with transport and temperature. Fast scopes need checking each session; slower ones hold for weeks.
- Central obstruction: The secondary mirror reduces contrast slightly. Imaging Newtonians use larger secondaries to fully illuminate a sensor; visual designs minimize them.
- Cooling: A large mirror stores heat and produces a boundary layer that softens detail until it equalizes. Rear fans reduce the wait considerably on Canadian nights.
- Dobsonian mounting: The most practical way to support a large Newtonian for visual use, at a fraction of an equatorial's cost.
Why Choose David Astro for Reflectors
A reflector is excellent value provided you are set up to maintain it, and we would rather tell you that beforehand.
- Collimation expectations set honestly: We tell you how often your specific focal ratio needs checking and recommend a tool that matches, so it is a two-minute routine rather than a chore.
- Coma corrector specified with the tube: For imaging Newtonians we supply the corrector and its spacing alongside the telescope, since the field is unusable without it.
- Focuser assessment: Stock focusers on fast Newtonians often cannot hold an imaging train squarely, and we will say when an upgrade is genuinely required.
- Authorized dealer: Full manufacturer warranty and verified authenticity, with service in Canada.
- Ships from Canada: Large optics delivered domestically with no duties or brokerage fees.
Reflectors in Canada — Frequently Asked Questions
- How often will I need to collimate?
- An f/4 imaging Newtonian benefits from a check every session. An f/6 visual scope typically holds alignment for weeks unless transported roughly. It takes about two minutes once you are practised.
- Do I need a coma corrector?
- For imaging below about f/6, yes — corner stars will show obvious coma otherwise. For visual use at f/5 and slower most observers are untroubled, though a corrector does improve the edge.
- How long does a mirror take to cool?
- A 200 mm mirror moved from a warm house to a Canadian winter night typically needs 45 minutes or more. A rear-mounted fan blowing across the mirror face reduces that substantially.
- Are reflectors good for planets?
- Yes, given aperture and good collimation. A well-collimated 200 mm Newtonian shows excellent planetary detail; the central obstruction costs a little contrast that extra aperture more than repays.
Considering a Newtonian?
Tell us whether it is for visual or imaging and we will specify the tube, corrector and tools. Canadian stock, worldwide shipping.