Re. great optics, I think that's especially the case with telephoto lenses, I don't think there's any workarounds to make them highly portable?
I'd not heard of that Leica before, but it does look amazing.
I'd not heard of that Leica before, but it does look amazing.
Mirror lenses have been around for a long time. They fold the length of larger telephotos into about a third with some trade-offs in speed and image quality.
[1] https://global.canon/en/v-square/34.html [2] https://www.usa.canon.com/internet/portal/us/home/products/d...
Another 'workaround' is the use of a mirror, but these lenses are only useful for very specific tasks and are usually not designed for the high end market.
https://www.kenrockwell.com/canon/lenses/70-300mm-do-is.htm
I agree with Ken Rockwell's review of the lens except I add that it just doesn't have the color and contrast "pop" of equivalent lenses such as the 100-400 L II zoom. One thing, though, the used price for the DO lens is low.
Is the image quality as good as my full sized Nikon gear - definitely not. Can I take more pictures that I couldn't even attempt before (wildlife and landscapes) - definitely.
Canon tried a fresnel lenes there "DO" series. Not quite as good quality at about half the size and way more money. Its interesting technology.
You can see the lens size comparisons near the bottom of this article.
https://www.the-digital-picture.com/Reviews/Canon-EF-400mm-f...
One of the main things driving larger optics/ is the amount of light the lens lets in. EG: max aperture (a lower f number) means bigger lens, more money. The availability of digital sensors means often you can shoot with higher film speed and might not require as large a max aperture..
The big difference from contemporary Samyang and Rokkinon catadioptrics is it's really long focus throw. It's about 350 degrees from 1.5m to infinity. At 500mm even f8 is shallow. Hyper-focal distance is over a kilometer on a crop sensor.
Even with a 2x teleconverter (1000mm f16/t22) it's less than a kilogram so it's easy to walk around hand holding and throwing it in the bag is not a major commitment.
Like any other lens it's a compromise. I live with it's technical shortcomings because it provides a specific capability to make images I would not make otherwise. In theory, it's a choice between lenses based on technical specifications. In practice it's a choice between making image with the catadioptric and no image at all. The images that would not exist otherwise exist because I can see in 500mm prime before I raise the camera and when my eye hits the viewfinder I'm not making a "well maybe I can crop it" compromise.