Askar 103 - 103mm f/6.8 APO ED Triplet Refractor

The Askar 103APO is a Triplet Refractor OTA with a 103mm aperture, 700mm focal length, and a 6.8 native focal ratio. The 103APO adopts a triplet air-spaced APO lens design and contains one piece of extra-low dispersion, also known as ED, glass to reduce chromatic aberration and reduce stray light.

The Askar 103APO has a detachable lens tube design.  With the rear segment lens tube removed, the 0.6x reducer can be attached to reduce the overall focal ratio to f/4. Removing this rear lens segment also allows the use of a binoviewer for visual observation.  While a good number of imaging astrographs made today are not designed for visual use, the Askar 103 APO refractor can come to focus with a 1.25" or 2" diagonal as well.

In terms of mechanical design, the Askar 103APO features two finder bases, a special slotted handle, a 290mm Vixen-style dovetail plate, a large 3.3" dual-speed rack-and-pinion rigid focuser, 360° high-precision graduated rotator, and overall CNC machining with anodized and painted finish.

The sliding dew shield's interior is lined with felt to reduce light scatter and reflections.  A dew shield helps keep dew from forming on your optics, but it also keeps external light from skipping across the lens and lowering contrast.

There are a total of two finder bases on the Askar 103, one on each side of the focuser. Many users have expressed concerns about the limited space for installing additional astronomical accessories. To address this, Askar specially set finder bases on both sides of the focuser. This not only eliminates the need for disassembly when changing the position of the finderscope but also provides additional mounting positions for other astronomical accessories.

The handle of the Askar 103APO has a special slot design, making it also a base for installing a finder scope. The handle itself is sturdy and durable.

The overall design of the tube rings is lightweight, with a total weight of only 750g. The thumb screw of the tube ring allows for easy opening and locking. At the same time, the raised base creates more space to accommodate astronomical accessories. In everyday use, the convenience of each step is taken into consideration.

The dovetail plate is the standard Vixen dovetail plate, compatible with most equatorial mounts and bases on the market. Askar has also made additional extensions and hole position designs, the length reaching up to 290mm, making it more convenient for balancing on the equatorial mount. With the slot on the handle, the spacing between the tube ring can be adjusted as desired. Additionally, there is also a Losmandy dovetail plate available for purchase, to be used with different (larger) equatorial mounts.

The Askar 103APO is equipped with a dual-speed rack and pinion 3.3" focuser, which is compatible with most motorized focusers on the market. There is also a high-precision scale and 10cm focusing travel. The entire focuser barrel is CNC machined with an anti-reflective internal design and matte paint, providing extra measures to eliminate stray light.

The rear of the focuser features a 360° high-precision big rotator, along with precise scales for convenient adjustment and saving of rotation angles, enabling precise rotation. It is also equipped with an enlarged rotator locking screw that can easily secure even under high loads.

The Askar 103APO  has three optional advanced accessories, a 1x flattener, an 0.8x reducer, and an 0.6x reducer. All three accessories are sold separately and come with built-in 2" filter threads for direct filter mounting and use. In addition, all three accessories are equipped with M54/M48 adapters, and the 0.6x reducer comes with an additional M68 adapter for easy attachment.

Specifications

• Aperture Size:  103 mm
  
• Focal Length:  700.4 mm
  
• Focal Ratio:  f/6.8
  
• Objective Lens:  Triplet air-spaced APO with one ED element
  
• Total Length:  600 mm (contracted), 711 mm (extended)
  
• OTA Weight:  4.75kg
  
• OTA with Tube Ring & Dovetail Weight:  5.5kg
  
• Rear Thread Type:  2"/1.25" Visual Adapters
  
• Included Accessories:  Pair of tube rings, handle, 290 mm Vixen dovetail plate