Nikon Df with 85mm f/1.8 compared to GH5 with 45mm f/1.8 (90 mm equiv)
The Df is Nikon's smallest and lightest full frame DSLR. It's taller at the viewfinder hump than the GH5, but otherwise the two cameras are pretty close in size and weight. The Olympus 45mm f/1.8 lens is just 5 mm longer as far as the focal length goes, so it's fair to show the size differences in the lenses. The lenses are where you see the most difference in size regarding full frame or APS-C vs. m4/3. The GH5 is a very comfortable size and has great handling, so I'm not one bit annoyed by the size. It's great actually. Who wants to hold a slim rectangle with no grip? Not me.
