Askar f/3.9 Full-Frame Reducer for FRA400 and FRA500 Flatfield Astrograph

Askar f/3.9 Full-Frame Reducer for FRA400 and FRA500 Flatfield Astrograph

The ASKAR full-frame 0.7x focal length reducer improves the FRA400´s and FRA500´s focal ratio from f/5.6 to f/3.9, halving the exposure time
Manufacturer : TS Optics
SKU : TSO-FRA400Red
Price: 251.26 € excl tax
Delivery date : 1-4 days
Askar F3.9 full-frame focal reducer

The new Askar FRA400 F3.9 full-frame reducer reduces the effective focal length of the telescope by a factor of 0.7x. The original f/5.6 apo becomes an f/3.9 apo. Its exposure time is significantly shorter, it is reduced to about 50%. The field of view becomes considerably larger.

The FRA400Red was developed for use with the FRA400 and FRA500 flatfield refractors and offers good correction with these telescopes, even when full-frame size sensors are used. The working distance from the M48x0.75 thread to the camera sensor is 55 mm. The camera adapter is equipped with a 2" filter thread.

Scope of Delivery:
  • Reducer
Products specifications
Recommended distance from focal plane to connecting thread55 mm
Focal length reduction0.7 x