Interesting tread I must have somehow mist this one before. I have a couple of Canon DSLR cameras and a handful of L-series lenses which altogether weigh in at around 7kg. Their great cameras and the picture quality is fantastic, just wish the operator was as good. But because of the weight I don't take them on any of my long walks which is a shame as that's where I take many of my best shots. For my long multi-day walks I have been using a simple compact and just accepting the limitations. recently I've been reading about the "new" mirror-less cameras (new as in they've only been around ten years).
As a result I have just brought a new Canon EOS M50 camera, same size sensor as in the Canon 50D/60D/70D series but much smaller body. Because there is no mirror or prism it's not "through the lens" so it has an "electric viewfinder" I'm not sure how they work but you use them just like a normal viewfinder. It also has a flip out touch screen so you can use either. I have the 15-45mm lens which is also very small and light, there is an adapter for using canon's other EF lenses on this camera but I haven't got one yet. By comparison my EOS 5D with a 50mm lens weighs 1220g. My EOS M50 with the 15-45mm lens weighs 495g.
It only came two days ago so I've not really had a chance to use it yet, hopefully the picture quality will be up to Canon's usual standard.