IanKingimaging

A 12" F8 carbon fibre truss tube Ritchey Chretien astrograph, 100% designed and manufactured in UK/Europe, to the highest specification.

The Altair DeepField Ritchey Chretien design is a professional observatory grade imaging instrument, suitable for schools, colleges and universities, or advanced amateur astronomers who want the best quality on the market. The complete design has taken over a year to complete and test, having been through two iterations.

Altair have chosen a truss-tube design because of the better thermal characteristics afforded by air circulation around the optics, almost eliminating the contrast-robbing effects of boundary air current layer formation, as well as allowing the optics to come to thermal equilibrium faster. This is also an extremely rigid design, which ensures optimum performance for the most demanding imaging requirements.

The two-element field flattener is dedicated to the particular spherical correction of the Altair Deepfield optical design at this particular aperture and is made in Europe in the same optical laboratory responsible for the mirror polishing and figuring.

Each optical set is generated and polished as a set and tested several times on a laser interferometry system, before coating in aluminium with a silicon dioxide overcoat. Each telescope comes with an optical test report which takes both primary and secondary mirrors into account as a complete system.

"Altair Astro DeepField Ritchey Chretien telescope optics are tested many times during production. The wave-front error of the complete optical system (consisting of both primary and secondary mirror as a set) must meet a minimum standard of at least 0.94 Strehl Ratio when exiting the focuser but without flattener). Each telescope is shipped with a screen-shot showing the final interferometric analysis of the wave-front produced by the particular set of optics in the telescope. This screenshot includes a computer-analysis of the wave-front produced on the test bench. Please note, in the interests of accuracy, astigmatism and coma values are not suppressed on the optical test report. Interferogram results can vary slightly with alignment of the optics when tested, ambient vibrations in the laboratory, and with random air currents - though precautions are of course taken to minimise these factors just as in any optical laboratory. The test report is to be treated like a photographic record, and each test report is unique to your telescope."

This is a special-order product. The January 2012 production run is already allocated, however more optical sets are in production which will be ready in March 2013. For more information, or for a special quote including camera, pier, observatory or robotic mount, please get in touch

A 10" F8 carbon fibre truss tube Ritchey Chretien astrograph, 100% designed and manufactured in UK/Europe, to the highest specification.

The Altair DeepField Ritchey Chretien design is a professional observatory grade imaging instrument, suitable for schools, colleges and universities, or advanced amateur astronomers who want the best quality on the market. The complete design has taken over a year to complete and test, having been through two iterations.

Altair have chosen a truss-tube design because of the better thermal characteristics afforded by air circulation around the optics, almost eliminating the contrast-robbing effects of boundary air current layer formation, as well as allowing the optics to come to thermal equilibrium faster. This is also an extremely rigid design, which ensures optimum performance for the most demanding imaging requirements.

The two-element field flattener is dedicated to the particular spherical correction of the Altair Deepfield optical design at this particular aperture and is made in Europe in the same optical laboratory responsible for the mirror polishing and figuring.

Each optical set is generated and polished as a set and tested several times on a laser interferometry system, before coating in aluminium with a silicon dioxide overcoat. Each telescope comes with an optical test report which takes both primary and secondary mirrors into account as a complete system.

"Altair Astro DeepField Ritchey Chretien telescope optics are tested many times during production. The wave-front error of the complete optical system (consisting of both primary and secondary mirror as a set) must meet a minimum standard of at least 0.94 Strehl Ratio when exiting the focuser but without flattener). Each telescope is shipped with a screen-shot showing the final interferometric analysis of the wave-front produced by the particular set of optics in the telescope. This screenshot includes a computer-analysis of the wave-front produced on the test bench. Please note, in the interests of accuracy, astigmatism and coma values are not suppressed on the optical test report. Interferogram results can vary slightly with alignment of the optics when tested, ambient vibrations in the laboratory, and with random air currents - though precautions are of course taken to minimise these factors just as in any optical laboratory. The test report is to be treated like a photographic record, and each test report is unique to your telescope."

This is a special-order product. The December 2012 production run is already allocated, however more optical sets are in production which will be ready in February 2013. For more information, or for a special quote including camera, pier, observatory or robotic mount, please get in touch.

This is a "fully loaded" version of the tried and tested 8" F8 Metal-Tube Ritchey-Chrétien with the following features:

A 2" Dual Speed Linear Bearing Focuser included as standard. It will handle a DSLR or CCD camera, and a light weight filter wheel perfectly well, and is adequate in most imaging situations. Note this focuser has the Linear Bearing upgrade, and will outperform most Taiwanese dual speed focusers, both in rigidity and pulling power. It is perfectly adequate for a DSLR/CCD camera and light weight filter wheel.

A Losmandy format dovetail plate and Vixen format bar are included, attached to the top and bottom of the optical tube.

You can now use one or more Altair TMS Vixen or Losmandy clamps clamps upside down (depending on the top bar type), to attach the rings to the underside and adjust the ring spacing to fit your guide scope without having to buy an additional dovetail plate. A small guide scope is perfect for this.

3x Heavy Duty Extension tubes included (2x 25mm & 1x 50mm) fitting between the focuser and the telescope. CNC Machined out of solid billet aluminium, zero flex.

Low expansion Quartz Mirrors with 96% reflective enhanced aluminium coatings with a Quartz overcoat (Silicon dioxide).
8" aperture true hyperboloid Primary & Secondary Mirrors.

Multiple internal light baffles line the optical tube.

Fast efficient cool down time compared to a normal SCT due to the open-tube design.
This telescope is designed with enough backfocus to use an off axis guider, AO unit and filter wheel. Therefore, to create the most rigid imaging train possible, instead of placing extension tubes after the focuser it's best to place them between the focuser and the rear mirror cell. Therefore 1x 50mm and 2x 25mm large diameter extension rings are included for this purpose, which can be placed between the focuser and telescope (with zero flex), for adjusting your backfocus.

Dimensions: OTA length 455mm Outside diameter 230mm Tube weight is 7.5kgs. The central obstruction diameter is 95mm

Click here to see the Altair RC Collimation Adjuster Plate

his is a "deluxe" version of the tried and tested 8" GSO / Orion / Astro Tech F8 Ritchey-Chrétien with the following features:

Now ships with 2 x Losmandy plates top and bottom.

•A 2" Dual Speed Linear Bearing Focuser included as standard. It will handle a DSLR or CCD camera, and a light weight filter wheel perfectly well, and is adequate in most imaging situations. Note this focuser has the Linear Bearing upgrade, and will outperform most Taiwanese dual speed focusers, both in rigidity and pulling power. It is perfectly adequate for a DSLR/CCD camera and light weight filter wheel.

•NEW feature: The base of the scope now has a light-weight Losmandy-format plate to fit the iEQ45 or other Losmandy-format mounts directly. This is more rigid than the channel type Vixen/Synta format dovetail bar found on other models.

A light weight Vixen/Synta type dovetail bar is included along the top of the telescope for guide scope attachment using the Altair TMS Lightweight Guide Scope Rings. You can now use one or more Altair TMS Vixen clamps upside down, to attach the rings to the underside and adjust the ring spacing to fit your guide scope. A small guide scope is perfect for this.

•Low weight low expansion Carbon Fibre OTA, weight 7.5kg! (16.4lbs) not only giving more accurate tracking but freeing up your mount capacity for other accessories. The use of a carbon fibre weave composite reduces the weight of the optical tube with no loss of strength or rigidity compared to an aluminium tube.

•Low expansion Quartz Mirrors with 96% reflective Enhanced coatings with higher reflectivity than standard mirror coatings on other versions of this scope.
•Optional field flattener available, optimised for this optical design.
•8" aperture true hyperboloid Primary & Secondary Mirrors.
•Multiple internal light baffles line the optical tube.
•Fast efficient cool down time compared to a normal SCT due to the open-tube design.
•This telescope is designed with enough backfocus to use an off axis guider, AO unit and filter wheel. Therefore, to create the most rigid imaging train possible, instead of placing extension tubes after the focuser it's best to place them between the focuser and the rear mirror cell. Therefore 1x 50mm and 2x 25mm large diameter extension rings are included for this purpose, which can be placed between the focuser and telescope (with zero flex), for adjusting your backfocus.

Click here to see the Altair RC Collimation Adjuster Plate

This is a "fully loaded" version of the tried and tested 6" F9 Ritchey-Chrétien with the following features:

A 2" Dual Speed Linear Bearing Focuser included as standard. It will handle a DSLR or CCD camera, and a light weight filter wheel perfectly well, and is adequate in most imaging situations. Note this focuser has the Linear Bearing upgrade, and will outperform most Taiwanese dual speed focusers, both in rigidity and pulling power. It is perfectly adequate for a DSLR/CCD camera and light weight filter wheel.

Two Vixen/Synta format dovetail bars are included, with one on top of the scope for guide scope attachment using the Altair TMS Lightweight Guide Scope Rings. You can now use one or more Altair TMS Vixen clamps upside down, to attach the rings to the underside and adjust the ring spacing to fit your guide scope. A small guide scope is perfect for this.

Low weight of about 5.5kg makes this the ideal portable long focal length imaging scope, freeing up your mount capacity for other accessories.

High quality BK7 Mirrors with 96% reflective enhanced aluminium coatings and a Quartz overcoat (Silicon dioxide).

6" F9 true hyperboloid primary & secondary Mirrors (1370mm Focal Length).

Multiple internal light baffles line the interior of the optical tube.

Fast efficient cool down time usually twice as fast as a normal SCT or Maksutov, due to the open-tube design of the RC.

This telescope is designed with enough backfocus to use an off axis guider, AO unit and filter wheel. Therefore, to create the most rigid imaging train possible, instead of placing extension tubes after the focuser it's best to place them between the focuser and the rear mirror cell. Therefore 1x 50mm and 2x 25mm large diameter extension rings are included for this purpose, which can be placed between the focuser and telescope (with zero flex), for adjusting your backfocus.

Rear of OTA to CCD approx 250mm

Dimensions: Tube length 390mm Outside diameter 198mm and weighs 5.4kgs and has a central obstruction of 77mm

Click here to see the Altair Focuser Collimation Adjustment Plate

The RC design is a true reflective design with no refractive optical elements. As such it provides superb light transmission.

The coma free field of this standard RC delivers wide flatfield performance on cameras up to the APS sized DSLR sensors.

Full format cameras require an optional corrector to achieve flat field performance.

The scope features a fixed primary and secondary mirror for flex free imaging. Included is a set of 3 thread on extension tubes to enable you to place your camera at the correct back focus distance for optimal performance. These thread between the scope and the 3" focuser - again for flex free performance.

The 3" Dual Speed Crayford focuser is a big jump in strength and rigidity from the 2" models and can easily accomodate DSLR and most CCD Imaging cameras.

This scope is a true Ritchey Chretien Astrograph and does not feature a full aperture corrector such as SCT and SCT design scopes.

The RC design is a true reflective design with no refractive optical elements. As such it provides superb light transmission.

This version comes with a carbon Fibre tube. The use of a carbon fiber weave composite reduces the weight of the optical tube with no loss of strength or rigidity compared to an aluminum tube.

**Please Note the scope features Losmandy Compatible rails fitted Top and Bottom**

Click here to read a review on the 10" RC
This true Ritchey Chretien astrograph is completely optimised for imaging. A pure two-mirror optical system means zero colour aberration and a large aperture with high resolution compared to refractors costing many times more. Because it has a fixed focuser, the primary mirror flop and resultant image shift issues often associated with long focal length SCT telescopes with moving mirrors are avoided. There aren't any complex internal parts to move the mirrors back and forth while attempting to keep them accurately aligned so there's less to go wrong. Another benefit of a high quality external focuser, is that the mirrors don't have to move relative to each other to focus the telescope, and so because everything remains in place, the focal point doesn't change outside the tube, making it easier for you to achieve repeatable, accurate focusing time and time again.

The coma free field of this standard RC delivers wide flatfield performance on cameras up to the APS sized DSLR sensors.

Full format cameras require an optional corrector to achieve flat field performance.

Included is a set of 3 thread on extension tubes to enable you to place your camera at the correct back focus distance for optimal performance. These thread between the scope and the 3" focuser - again for flex free performance.

The 3" LBF Dual Speed Crayford focuser is a big jump in strength and rigidity from the 2" models and can easily accomodate DSLR and most CCD Imaging cameras.

This scope is a true Ritchey Chretien Astrograph and does not feature a full aperture corrector such as SCT and SCT design scopes.

Click here to see the Altair Focuser Collimation Adjustment Plate

The new Sky-Watcher EXPLORER-130PDS Newtonian Reflector incorporates the same superb mirror-set as the Explorer-130P Black Diamond Series, but with two significant advantages.

A Dual-Speed 10:1 ratio focuser is now included for excellent focusing precision.

Also the tube length has been slightly shortened to optimise performance for prime-focus photography.

Even better performance for astro-photography and visual use can be achieved when used in combination with Sky-Watcher’s Newtonian coma corrector

Standard Specification:
Magnification (with eyepiece supplied) x23
Highest Practical Power (Potential) x260
Diameter of Primary Mirror 130mm
Telescope Focal Length 650mm (f/5)
Eyepiece Supplied 28mm (2"/50.8mm)
6x30 Finderscope
Parabolic Primary Mirror
2" (50.8mm) Dual-Speed 10:1 Crayford Focuser
0.5mm Ultra-Thin Secondary Mirror Supports
30% more Light-Gathering than 114mm

The Skywatcher Quattro series are premium quality imaging Newtonians with a wide field of illumination and fast f4 focal-ratios.

8-inch and 10-inch models are available with steel or carbon fibre tubes. Tube interiors have knife-edge ray traced baffles.
CARBON FIBRE TUBE: Carbon fibre is a strong and lightweight material with better thermal stability than steel. This is especially important for astro-photographers dealing with long exposure times. Imaging telescopes made of less thermally stable material can deviate from optimum focus after long time exposures. With a carbon fibre tube, it can remain in focus for a longer period of time.

2" DUAL-SPEED LINEAR POWER FOCUSER: The new linear power focuser utilises four precision ball-bearings to support the drawtube for excellent stability and zero image shift while supporting a heavy imaging camera and accessories. Moving the drawtube using a roller rather than a rack and pinion ensures an exceptionally smooth and precise focus adjustment. The dual-speed feature has a second focus knob with a 10:1 speed reduction for super-fine adjustments.

PYREX MIRRORS: All models feature paraboloidal primary mirrors made of low thermal expansion Pyrex glass resulting in shorter cool-down times.

NB: Like all fast Newtonians the Skywatcher Quattro series are best suited to experienced astronomers. They require precise collimation and a Coma Corrector to reach their full potential.