Περιγραφή
The FRA400 f/3.9 reducer was developed as a dedicated accessory for the Askar FRA400 / FRA500 astrograph. It guarantees excellent field correction, making it ideal for use with professional cameras and camcorders equipped with a full-frame matrix.
This reducer reduces the focal length by a factor of 0.7x, which in the case of the Askar FRA400 astrograph gives a value of 280 mm at f/3.9. Such parameters allow not only to take breathtaking photos in a wide field of view, but above all to shorten the exposure time by up to half.
This device allows the installation of filters with a diameter of 2″, screwed into the M48x0.75 thread on the camera side.
The most important features of the Askar f/3.9 reducer
- focal reducer dedicated to the Askar FRA400 and FRA500 astrographs, compatible with cameras and full-frame cameras
- 0.7x multiplicity giving an effective focal length of 280 mm at f/3.9 for FRA400 and 350 mm at f/3.9 for FRA500
- can be used with filters with a diameter of 2″
- 55mm back focus
