This Askar Astrograph is a cost-effective Newtonian telescope specially designed for deep-sky astrophotography. The fast optical system has an aperture ratio of f/3.6. When combined with the 0.95x coma corrector included in the package, this results in an even faster aperture ratio of f/3.4. The high-quality three-element coma corrector can be securely screwed onto the focuser and ensures optimal image quality right out to the corners of the frame.
The parabolic primary mirrors and the secondary mirrors are made of temperature-stable borosilicate glass and feature an aluminium coating. Tension and compression screws on the rear of the primary mirror cell allow for tool-free adjustment (collimation).
The secondary mirror is dimensioned to illuminate sensors up to APS-C format. Its tilt can be precisely adjusted using three adjustment screws.
A rack-and-pinion (R&P) extension with a fine-adjustment reduction mechanism is used for focusing. Once a screw has been loosened, the focuser can be rotated. This facilitates the optimal alignment of the camera and accessories, but does not replace a full-featured camera rotator. In addition, the base of the focuser features an integrated tilt adjustment (tilter), which allows the optical axis of the focuser to be precisely aligned with the optical path of the main optics. Thanks to the appropriate drill holes, the focuser is also prepared for retrofitting a focus motor.
Fine-adjustment rings (‘shims’) are included in the scope of delivery to ensure optimum back-focus adjustment.
Both the carrying handle and the viewfinder shoe offer simple mounting options for additional accessories. The telescope is mounted on a mount via a generously dimensioned prism rail in accordance with the Vixen standard.
Carbon lens tube: The classic black carbon lens tube saves weight. This not only makes transportation easier but also takes load off the mount. At the same time, the thermal expansion coefficient of carbon fibre is considerably smaller than that of aluminium or steel. This makes the telescope's focus much more stable when is comes to changes in temperature.
It not only matters which telescope you buy but also where you buy it. Our additional services:
- We are a leading telescope dealer and know the devices we sell. Our customer service team will gladly help you after your purchase if you have problems with assembly or operation.
- We provide a copy of the 80-page Telescope ABC beginners handbook with every telescope.
