Canon 300mm F4 L first proper test with EAF and asi camera

[powerlord]

Hi chaps, I bought this lens for astro, but in the early DSLR days. When I moved to astro cameras, as I couldn't fit the EAF, it got side lined though indications were that it would be good.

I finally got around to 3d printing a cage for it to fit my EAF at the weekend, and shot first light last night with my asi533.

I'll process that later, but for now, I had a quick look at a frame, and was truly impressed - tiny round stars edge to edge. I put it through CCD Inspector and got the below.

I bought mine 2nd hand of ebay for £350. You are getting an F4 300mm lens for that price. I remember, this is shooting wide open aperture as that's your only choice if not using with a DSLR.

I know I'm not the first to recommend this lens, but point me at a 300mm FL F4 APO OTA you can get for £350 second hand !