Askar 107mm f/7 Petzval Astrograph
The 107PHQ is the successor of the legendary TS 107/700mm APO. The manufacturer has further developed the apo and made a powerful astrograph out of it. Remained is the color-correct triplet objective with 107mm aperture. Due to the built-in corrector the field is very well corrected. You will have perfect star imaging in the field right from the start, without tedious searching for correctors and the right distance.
The apo provides perfect star reproduction on the optical axis and in the field and is also very good for visual observation. Magnifications up to over 300x are feasible, with good contrast.
The Askar 107PHQ is a real all-rounder with F/7
A telescope for almost all applications, that´s exactly what the 107PHQ is built for.
♦ With 740mm focal length and the large corrected field of view, extended objects can be imaged. But equally, fine details of objects can be brought out when cameras with high resolution are used.
♦ The use of different cameras with different flange focal lengths is no problem. Simply focus and you are always at the correct distance. The adapter battle is eliminated.
♦ The focuser has a large adjustment range, so you can find the focus without problems.
♦ The working distance or backfocus from the 2" Barrel is long enough to use 2" zenith mirrors. This turns the Flatfield Apo into a large field telescope or even a planetary telescope, depending on the eyepiece used.
The photographic 3.4" Rack&Pinion focuser:
The CNC focuser is optimized for photography and can handle a load of up to 8 kg. The adjustment range is very generous at 110mm. The focusing is done via gear drive. The gear drive is decoupled from the bearing of the extension tube. This guarantees fine and precise adjustment even at maximum load. In addition to the 1.25" and 2" Barrel, the focuser also offers threads for screw adaptations.
The back focus is always measured with the focuser tube completely retracted:
♦ 79mm from M48x0.75 male thread
♦ 99mm from M54x0.75 male thread
♦ 119mm from M68x1 male thread
♦ 149mm from M86x1 male thread
♦ 120mm from 2" connection
This is how we hand over the Apo to the star lover:
Each and every AS107PHQ Quadruplet APO is inspected in our engineering department before being stocked to ensure consistent high product quality.
♦ The mechanics are tested, the focuser is adjusted optimally.
♦ The objective is cosmetically checked and cleaned. In addition, it is checked whether all counter screws are correctly tightened. Often these loosen during transport.
♦ The optics are collimated and the result is checked on the optical bench.
♦ Only then are the telescopes transferred to the warehouse and prepared for shipment.
Technical Information
Teleskop-Service has collected a lot of helpful information about refractors and provided it in German language as a PDF file:
Refractors
