Askar F3.9 Reducer for FRA600
369.00
Tax included
Askar F3.9 Reducer for FRA600
The Askar F3.9 is a 3 inch optical reducer designed for the Askar FRA600 astrograph. It applies a 0.7x reduction, shortens the focal length to 420 mm and improves visual use and astrophotography efficiency.
Askar F3.9 Reducer for FRA600
Description
The Askar F3.9 is a 3 inch optical reducer specifically designed for the Askar FRA600 astrograph. Its optical construction is based on a four element design optimized for this instrument. With a 0.7x reduction factor, it effectively lowers the focal ratio and reduces the resulting focal length to 420 mm.
This reduction shortens exposure times and increases the usable sky area, providing greater flexibility for both visual observation and astrophotography.
The mechanical back focus is standardized at 55 mm, allowing straightforward integration with common imaging setups. The reducer features a built in M48x0.75 filter thread, enabling direct attachment of 2 inch filters without additional adapters. This design ensures practical operation and compatibility with standard astronomical accessories.
Technical specifications
Compatibility: Askar FRA600
Reduction factor: 0.7x
Resulting focal length with FRA600: 420 mm
Resulting focal ratio: f3.9
Optical design: four elements
Mechanical diameter: 3 inch
Back focus: 55 mm
Filter thread: M48x0.75
Use: visual observation and astrophotography
Askar Réducteur F3.9 FRA600
1 Item
Askar F3.9 Reducer for FRA600
The Askar F3.9 is a 3 inch optical reducer designed for the Askar FRA600 astrograph. It applies a 0.7x reduction, shortens the focal length to 420 mm and improves visual use and astrophotography efficiency.