Astronomy Specialist

ASKAR FRA300 PRO F/5 APO REFRACTOR

$1,031.00 USD
SKU: AS-FRA300

Askar

Apochromatic Petzval quintuplet

60 mm

f/5

300 mm

3.12 kg


 

The Askar FRA 300 f/5 Pro is a professional apochromatic Petzval quintuplet with an aperture of 60mm and a corrected field of 44mm in diameter.

The lenses are assembled in two groups: an air-spaced triplet on the front and two far-separated corrective lenses in the rear. The objective lens includes one Extra Low  Dispersion lens for superb chromatic correction.

 

 

Differently from standard ED refractors, the Askar 300 features a Petzval design that does not require to set the sensor to a specific distance to the last lens. That leaves the freedom to use any filter wheel, any off-axis guider or accessory without any worry to calculate the correct distance from the flattener. 

 

 

With a large 44mm corrected image circle and a fast focal ratio of f/5, this is the perfect astrograph for the advanced astrophotographer. The large rack and pinion 2.5" focuser has a high payload capacity, it can be rotated 360° to perfectly frame the subject and it has a reduction gear of 10:1 for precise focusing.

All the lenses are fully multi-coated and the tube is internally blackened to reduce reflections and absorb stray light. The tube is made of aluminium, the rack and pinion focusing mechanism of brass and the mechanical components are engineered to provide the best rigidity, performance and durability.


 

 

 

Optical design

Apochromatic Quintuplet air spaced with one ED element

Objective diameter

60 mm

Focal length

300

Focal ratio

f/5

Image circle

44 mm

Mount attachment

300 mm Vixen style bar

Focuser

Rack & pinion dual speed (10:1) 2.5" diameter

Camera connection

M54 x 0.75 male, M48 x 0.75 male, M42 x 0.75 male

Backfocus

71 mm from base of M54 & M42 threads, 67 mm from base of M48 thread

Tube weight

3.12 kg (including tube rings and dovetail bar)

Tube length

303 mm

Tube diameter

TBD

Dew shield diameter

TBD

SKU

AS-FRA300

 

 

 

  • Askar FRA300
  • Tube rings
  • 300mm Vixen style dovetail bar
  • Handle on the rings
  • M54 x 0.75, M48 x 0.75 & M42 x 0.75 imaging adapters
  • Manual


ZWO camera software ASKAR FRA300 manual (coming soon)

 

 

 

 

 

Askar FRA 300 Pro + ZWO ASI6200MM, LRGB.

Customer Reviews

Based on 3 reviews
67%
(2)
33%
(1)
0%
(0)
0%
(0)
0%
(0)
J
John O'Mahony
Askar FRA300 Pro

I have only had a chance to use it once to date. It is flat across the field in my 2600 MC Pro camera. Tiny bit of CA at the edges but its well controlled and only visible to the pixel peepers. It is well built-not quite William Optics levels but very good. It is sensitive to focus shift as the temperature drops so an EAF is recommended for long exposures, which I now have and is easily attached to the focuser. A good scope to consider against a Redcat 51 if you like a tradition focuser.

S
Stuart K
Askar FRA300 - Great Buy

Extremely impressed, exactly what I was looking for in a wide field astrophotography telescope, as a step up from standard camera telephoto lenses. Image sharp across entire frame with no colour distortions. The telescope exceeded my expectations, which is rare when I purchase items, would recommend to anyone looking at this focal length.

N
Nick Axaris
Great little scope with a geniune flat field

Amazing little scope with a great flat field used in suburban Melbourne. Negligible CA and sharp edge to edge.

ASKAR FRA300 PRO F/5 APO REFRACTOR.

ASKAR FRA300 PRO F/5 APO REFRACTOR

$1,031.00 USD

Optical design

Apochromatic Petzval quintuplet

Image circle

Focal ratio

f/5

Aperture

60 mm

Focal length

300 mm

Optical thickness

Threads

Cooled

Colour or Mono

Pixel size

Sensor dimensions

Resolution

Sensor diagonal

Quantum efficiency

Read noise

Fullwell capacity

Bit depth

FPS

Camera backfocus

Filter size

Filter size

Bandpass (FWHM)

Bandpass (FWHM)

Glass thickness

Mount type

Payload capacity

Latitude range

Dovetail saddle

Slew speed

Encoders

Periodic error correction

Counterweight shaft

Azimuth adjustment range

Internal diameter

Illuminated diameter

Compatible telescope external diameter

Weight

3.12 kg

Length

Width

Height

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