I was joking... kind of, but it's a serious joke. Here's the Fujinon 180mm F/3.2 EBC GX-D. I don't have the lens or brochure here, but it's around a kilogram:
It was made for this camera, here with another lens:
The GX680 is 2-2,500 kg depending on type and configuration. It's a beast, and so are the lenses. When this camera was launched, early nineties, a typicical high quality portrait lens, like a Nikkor 105mm f/1.8 or Contax/Zeiss 85mm f/1.4, where 5-600g, in spite of all metal construction and old technology. So 35mm format offered something medium format couldn't: smaller lenses which was traded for a reduction in image quality and resolution. Still, most people preferred the smaller format, for practical and cost reasons.
Panasonic and Olympus have been criticised for the size and weight of some of the high end lenses for m4/3. The Zuiko 45mm f/1.2 and PL 42.5mm f/1.2 (with OIS) are both just over 400g. The latest full frame 85 and 105mm offerings from Sony and Nikon are 8-900g. Sigma has gone further and can be found between 1,100 and 1,600g. The reason for the big lenses is clear: more pixels dictate higher quality lenses, which seems to mean bigger. So the 4/3 format offers something the 35mm format can't: smaller lenses which is traded for a reduction in image quality in low light, but mostly not in resolution, since most cameras are between 20 and 30 MP anyway. See where this is heading?
Yes, I can in some cases buy smaller lenses with smaller apertures for full frame cameras, but where's the advantage of the larger format then?
Ironically, the small camera bodies that most mirrorless brands now offer have a limitation: ergonomics are not ideal for certain types of photography. Panasonic understood that years ago and launched the GH3, then the GH4, GX8, GH5 and G9, all of them much larger than their sensor size should dictate, but with fantastic ergonomics and build quality.
F.FWD. to 2019 and we'll have the Olympus E-M1X. This camera seems to have so much EOS 1D/D1/2/3/4/5 DNA that Canikon should sue Olympus for copyright infringement. :wtf: It's the kind of camera that sports photographers learned to love with the Nikon F5, just a bit downsized. What it does not offer are the $12,000, 3 kg+ lenses that sports photographers hate after 30 minutes at the race circuit, the lenses that make you go home 30 minutes early, missing the last minute crash at sunset, the lenses that you don't bring to the highest peak because they're too heavy, making you miss the shot of the only living sample of the Pink Headed Eagle that happened to fly by that morning.
No, CaNiSony won't die because of this. Not this year anyway. But things will change, and they'll be forced to introduce higher grade APS format mirrorless cameras. Canon and Sony already have suitable lens mounts for that. Nikon doesn't. I wonder what they'll do. Maybe the D500 is good enough?
Sorry for the rant, but I'm surprised that so many in today's world, with an industry that has been turned upside down the last 20 years, still think that things won't change. They will.
Fuji is on the right track though. As usual