Now, we have full-frame mirrorless cameras from Sony, Nikon, Canon and Panasonic. Does that give an indication of the decline of full-frame DSLR cameras? We need to wait and see. Sony is the first manufacturer to launch the full-frame mirrorless and they are quite successful with their high-end model Sony a7R III. Let us see who wins in the battle of Full-frame Mirrorless Cameras Vs Full-frame DSLR Cameras.