Earlier quoted context omitted.
Traditional lens manufacturing is likely in its last days (which can easily take a decade or two, but ... the end is visible). Modern lens are made with techniques perfected in semiconductor manufacturing, and use advances in material science (meta materials in particular). I don't know how close this is to mass market, but I've seen superthin flat lens, with a marginal cost of production around ~$2 in a university f…
There's a couple of lens advancements I've seen recently that I found particularly interesting: Canon putting Fresnel elements in their lenses to reduce size/weight: https://kenrockwell.com/canon/lenses/400mm-f4-do-is-ii.htm Canon making an f/11 800mm super telephoto lens that can still autofocus thanks to the new mirrorless camera bodies: https://www.kenrockwell.com/canon/eos-r/lenses/800mm.htm I think we'll see a b…
Aside, I enjoy that Ken also loves this lens, despite it being mostly plastic, which he usually shits all over. It actually seems like a feature here, for weight purposes.