Astronomy Specialist

SKYWATCHER PHOTOGRAPHIC NEWTONIAN 250 F/4.7

$1,199.00 AUD
SKU: SW25012AP-OTA

Sky-Watcher

Newtonian

254 mm

f/4.7

1200 mm

14.38 kg


 

The SkyWatcher 250 f/5 photographic Newtonian telescope is optimized for astrophotography. In fact, its oversized secondary mirror provides a large illuminated field that is ideal for large camera sensors.

This telescope has a fast f/5 focal ratio and while the coma is still visible, it is 36% lower than the coma in a Newtonian f/4. This allows for the use of the photographic reflector on visual observations and high resolution imaging of planets and the moon.

The optional SkyWatcher coma corrector for f/5 Newtonian corrects the coma superbly, offering a large corrected field for astrophotography.

The 2" Crayford focuser is solid, precise and backlash free. It operates at two speeds due to the 10:1 reduction mechanism for an extra fine focusing adjustment, which is paramount for astrophotography and high resolution observations.

The oversized secondary mirror is collimable by using 3 grub screws and the offset can be adjusted by using the central spring loaded screw.

The primary mirror is collimable with 3 pairs of push & pull screws. 

The aluminium tube is internally blackened to avoid internal reflection, enhance contrast and to absorb stray light.

 

  

 

Optical design

Newtonian reflector 

Objective diameter

254 mm

Focal length

1200 mm

Focal ratio

f/4.7

Secondary mirror

63 mm (minor axis)

Linear obstruction

25 %

Resolving power

0.47 arc second

Stellar limiting magnitude

14.0

Max. magnification

508 x

Light gathering power

1317 times the human eye

Mount attachment

Tube rings on Vixen style bar

Focuser

Crayford dual speed (10:1)

Tube weight

14.38 kg

Tube length

1120 mm

Tube diameter

288 mm

SKU

SW25012AP-OTA

 

 

  • Newtonian 250 f/5
  • Tube rings on Vixen style bar
  • 8x50 finderscope
  • Eyepiece LET 28
  • 2" to M42 and 2" to 1.25" all in one adapter
  • Piggyback 1/4" screw with camera locking nut

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    SKYWATCHER PHOTOGRAPHIC NEWTONIAN 250 F/4.7.

    SKYWATCHER PHOTOGRAPHIC NEWTONIAN 250 F/4.7

    $1,199.00 AUD

    Optical design

    Newtonian

    Image circle

    Focal ratio

    f/4.7

    Aperture

    254 mm

    Focal length

    1200 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

    14.38 kg

    Length

    Width

    Height

    View product