Today Sharpstar announces the newest addition to its Askar FRA series, the Askar FRA600/5.6. Following the excellent optical performance of its first FRA400/5.6, the FRA600/5.6 is an evolution of the FRA series, an upgraded lens has a 108mm aperture and a 600mm focal length, the f/ratio is still f/5.6, and the image circle is 66mm surpass the full frame!
For more information, please go to Askar official website to check, click here to jump.
This FRA600 Quintuplet Refractor is also built on a Petzval design, offering a front triplet and rear doublet lens constructed of 5-element, includes two ED elements. This combination provides a high level of apochromatic performance for astroimaging.
With wonderful optics design, the FRA600 telescope provides a 66mm image circle to ensure excellent star shape across the entire flat field whilst controlling chromatic aberration, minimizing the distortion.
The two lens in the rear group have a 80mm diameter, effectively reduces the occurrence of decreased field illumination. With the precision lens manufacturing, it obtains theoretical optimal pinpoint stars, bringing you beautifully round stars and clean detail image.