ASKAR SQA85 f/4.8 APO QUINTUPLET f/3 280 mm diameter Schmidt Cassegrain

280 mm diameter Schmidt Cassegrain (C11) and similar

this is milled from solid aluminium for strength and rigidity

It also works with the QHYCFW3S Small filter wheel

This improves the image contrast significantly and the brightness shades are smoother and more natural

ASKAR SQA85 f/4.8 APO QUINTUPLET f/3 280 mm diameter Schmidt CassegrainThe Askar SQA85 is an apochromatic quintuplet flat field astrograph that offers high performance thanks to its air spaced SD lens design. The self flatted Petzval lens design supports a 44mm image circle with a central RMS star size of only 1. 6m. Stars at the corners of a full frame sensor are tiny at just 2. 5m. Thanks to its Petzval design, you don't need to worry about reaching a precise backfocus distance. As long as you're in focus, you're good