Sunagaor 500mm

Hi all.
I've been given the chance to buy a Sunagor 500mm f8 telephoto lense with M42 mount and K mount converter. It's a "normal" telephoto rather than a mirror lens.
What are these lenses like? Anyone had any ecperience? They only want £20 so thought it worth a punt - but bearing in mind how large it is don't want it to just sit around in a draw not being used if it is not a reasonable lens.
Cheers
Donut

might be worth a punt for £20, but I'll be very impressed if it's any good.

Even if it's optically fine, these old lenses tend to be big, heavy and slow. F8 will make it a pain to focus. You will need a sturdy tripod and you wont want to be lugging it around much.

if you can find a t mount adaptor for it and a tripod collar, it might get some use as a spotting scope or telescope, for the kids...

It's got a tripod mount already. Sounds as though it may not be worth the hassel though - especially regarding the weight.
Cheers
Donut

I used to have one of these 25 years ago

It's big and heavy, but reasonably sharp.

The problem I had with it was keeping it still - I never had a tripod heavy enough for the job.

If I were you, I would give it a miss...

R