The 5DSR packs a 50.6 megapixel sensor into a familiar DSLR body. This means you get images with resolution rivalling some medium format systems, while still being able to use the huge range of EF mount lenses, an advanced autofocus system, and a familiar workflow.
The Canon 5D mark IV has a newly designed full frame sensor giving a highly detailed 30.4 megapixel image. The new sensor also gives you 4K video up to 30fps and 1080p video up to 60fps. Other new features include Wi-Fi, GPS, NFC, in-built intervalometer, dual pixel autofocus and a new 3.2” touch screen.
The Canon 5D mark III is the DSLR of choice for many professionals. Resolution is similar to the mark II but stills and video image quality are improved with a better sensor. It has a new 61 point autofocus system, improved video compression and faster continuous shooting.
The EOS 7D is has a 19-point AF system, magnesium alloy construction, a large bright viewfinder, full HD movie recording, 8 frames per second continuous shooting, and many more features for professional use.