The Askar FRA400C offers a refreshed take on the popular FRA400, optimizing it for both astrophotography and terrestrial use with a camera-lens inspired design. Sharing the same 72mm aperture, 400mm focal length, and quintuplet Petzval optical system as the standard model, it delivers the same flat-field performance across a 44mm image circle but with distinct mechanical features.
Unlike the standard telescope version, the FRA400C is equipped with a smooth helical focuser for precise manual focusing, similar to a high-end camera lens. It also features an adjustable aperture diaphragm (f/5.6 to f/22) with 17 blades, allowing for depth-of-field control during daytime photography or specific imaging applications.
The 5-element optical design, including two ED glass elements, ensures excellent color correction and sharpness without the need for a separate field flattener. This "plug-and-play" performance simplifies setup, as there is no need to calculate specific back-focus distances within the connection range—simply focus and shoot.
Weighing 2.68kg (3.18kg with accessories), the FRA400C is compact and portable. It includes a comprehensive set of rear adapters (M72, M54, M48) for camera attachment and is equally capable as a visual telescope using the included eyepiece adapters. An optional 0.7x reducer is available to boost the speed to f/3.9.