For example the Nikon Z 50mm f1.2 is 1090 grams, 150mm long, and has a 82mm filter size. The Canon RF 50mm f1.2 is 108mm long, but the other dimensions are similar.

Compare that to a Leica Noctilux 50mm f1.2 with a Techart, Megadap or similar adapter (available for Z and E mounts) for autofocus abilities: 405g lens +150g adapter = 655 grams, 52mm lens + ~11mm adapter = 63mm long and 49mm filter size. A little more than half the numbers in all dimensions.

This link approximately shows the size differece (the M to L mount is indeed smaller than the M to Z or M to E autofocus adapters, but the difference is small)

All of these have the same focal length (50mm), max aperture (1.2), and autofocus. So why do these newer mirrorless lens designs have to be so much bigger and heavier than using an old manual lens with an autofocus adapter? Sure the autofocus speed may not be as fast with an adapter but why can’t they design a native autofocus large aperture lens that is tiny like the Leica M lenses. Clearly it is possible to do so.

  • @aarrteeBEnglish
    1•7 months ago

    this is a very good question.

    i imagine that the physics of lenses and light play a part in this…

    i wonder how much of this is a business decision?

    i wanted to compare two of my better lenses… the tiny EF-M 32 mm f/1.4 and the very big and very heavy EF 85 mm f/1.2

    i put the camera on f/4 and positioned the cameras so that they had approximately the same field of view of this $100 bill. I focused in the middle of Ben Franklin’s face.

    i adapted the EF lens onto the M6 MkII: I wanted the same camera capturing the images. the angles of view may be slightly different. Contrast and sharpness? They look awful darn close to me.

    The EF-M lens cost me a few hundred. the EF 85 cost me one or two thousand.

    https://www.flickr.com/photos/73760670@N04/albums/72177720313024348/with/53362824792/