[moe mountain mike]

i have a few mirror lenses. sakar 500 mm 1:8, quantaray 500 mm 1:8, quantaray 300 mm 1:5.6. i used them on pentax k1000, d100 & d200. the 300 mm is/was/will be the best. the quant 500 i have is very bad. it suffers from astigmatism. the sakar 500 is actually pretty decent at around 25 feet. i found this out by using them on a sony ilce 5000. 5x focus assist magnification is super helpful. that explains the unusable results i got with non live view older [D]SLRs.

i find mirror lenses great for video [even low IQ], HD, 720, 480. i dont think most common mirror lenses can handle 4K. spotting ships at sea, the moon, zoo animals. nesting birds, anything that you can set up a tripod and point camera at. if you have a good copy dont be afraid to use a 2x tele converter. USE A LENS HOOD!

many newer pentax DSLRs have live view. what i did here applies to them. i am warning you. you will be buying lots of mirror lenses to get a good copy. as long as you can get them cheap or free it's worth the cost to get the good one. the 300 mm amazes me. crisp sharp focusing compared to mushy undefined focus with the others. the 300 is compact. even with 2x converter shorter than the 500's.

the build quality on sakar is marginal. the quantaray's seem to be a step up. of course the canon 500 mm 1:8 FD is top notch mechanical and IQ..
youtube playlist of various combo's of the above lenses.
"CAT" mirror lens shoot out! - YouTube

[BigMackCam]

Thanks for posting this

I highly recommend the Soviet ZM-5SA ("ЗМ-5СА") 500mm f/8 in M42 mount, which can be picked up for under $100 (mint examples with filters and case for maybe $20 - $50 more). If you get one that's been well looked after and not re-assembled poorly after servicing (which can result in distortion of the mirror), it's capable of really excellent IQ. Plus, the build quality is truly excellent.

And "yes"... Live View is pretty much essential for DSLR use. A mirrorless camera with EVF makes life easier still...

[TaoMaas]

i find mirror lenses great for video [even low IQ], HD, 720, 480.

I've got an old 500mm Soligor CD mirror lens that I've been using for video. Originally I just tossed it in the bag so that I'd have a really long lens available. I usually say, "Just in case I see Bigfoot." When I actually had to pull it out and use it, I was surprised at the results. For the size and cost, it was well worth having.