Soligor Mirror Lens 500mm
I purchased one of these behemoths from someone on Facebook Marketplace. And when I opened the case it was way larger/fatter than I anticipated. The photos in the listing really needed a banana for scale. I'm fresh out of bananas so I've mounted it to a Nikon D3000 to it to give you some sense of scale. You do have to get a T-mount adapter to mount it to your camera but I was able to pick one up for about $10 off Amazon.
Commonly referred to as a mirror lens, these are catadioptric optical systems that use refraction and reflection to get the 500mm distance in a relatively compact form factor at a low price. It's basically a little semi-portable telescope. Trust me, you don't want to be walking around with this hanging from your neck all day. Additionally, the technology behind it is very basic and all manual so you do not get any vibration reduction or autofocus. And the image is soft but you get what you pay for.
For comparison, to get that 500mm distance in something modern and sharp the Nikon NIKKOR 200-500mm will set you back nearly $1,400. But for that you get razor sharp images, vibration reduction, and auto focus.
I bought the Soligor out of curiosity and look forward to playing with it. I took a few handheld shots to share what the image quality looks like so you know what to expect if you're looking to get a mirror lens. I'm always fond of the compression you get with a zoom lens but the size and softness of the image will mean this isn't a lens I'll be using very often. In the gallery below you an see that light in the bokeh has a circular shape, a telltale sign that the photo was captured using a mirror lens.
Let me know if you shoot with a mirror lens. I'm curious if many people still use these.