Looks like I haven't used any of my cats for quite some time.
http://oh-hi.info/2011/?from=2011-01-24.jpgSomewhere around here I was using my sigma 600mm/8 that ive had since the 80s, it has fairly bad aluminium coating separaton on the front mirror...so pretty much everything that says 600mm suffers from bloom and softness. (click the images for the exif)
Later you'll see i start using the ZM-6A 500mm f6.3 - thats a nice lens, but heavy and you may need to do minor surgery on its rear optics to put them in the right arrangement.
The other 500mm f/8 is a Tamron Adaptall2 SP 500mm f8 mirror 55BB - also nice lens, small and weightless, silky focus. But dark as fuck to look through because small objective diameter, so focusing and even being able to see through it can suck a bit.
Occasionally you may see a 1000mm, thats either SMC Pentax Reflex 1000mm f11 or MTO-11CA__MTO-11 1000mm f10. Both pretty nice, but very niche and cumbersome.
BTW: if you are using a regular focusing screen with any catadioptric you are doing it wrong.
Get
https://focusingscreen.com/ to cut an "A TYPE : Canon Super precision matte Eg-S" screen to fit your camera. Yes really. Regular digital screens are brighter, high contrast screens are darker but thats what you need to see focus contrast on a cat properly. Prisms and hemispheres are the worst possible thing you can use on a catadioptric because they suddenly turn black in even half decent light.
