I have finally upgraded my digital camera, which I use to walk around with on the poodlewalks and for scoping for my large format photography. It is a full frame, interchangeable lens Sony A7r111 mirrorless camera, and it was dam expensive. It cost just over $A5000 as there were no trade in bonuses or cash backs. This is a lot of money for me (pretty much the limit of what I can afford) and it will take me the rest of the year to pay it off. If I lose the Sony A7r111, the overall replacement cost with the Leica 35mm lens would be around $11,000, which is way beyond what I can afford. This kind of expense puts it out of reach of not just "amateurs" but enthusiasts as well.
We do pay a premium for the incremental improvements in new technology--eg., a fully loaded 5K iMac. The new technology--cameras and computers--- is overpriced and there is a relentless upward price of computer and camera gear. Fortunately, I was able to attach the 35mm f2.0 Leica manual focus lens and the Novoflex adaptor that I used to use on the Sony NEX-7. The Sony/Leica combination worked well for me in the past, and so far it is even better with the A7r11.
The Sony NEX-7 will now become a back up walk around camera with macro capability, once I acquire the necessary Voigtlander close focus adaptor, and find another Leica M lens to use.
The NEX-7 which I had used for over 7 years does feel like a toy compared to the A7r111. Sony have come a long way since 2011. The A7r111 feels like a professional camera: it is much more solid, better built, has a bigger battery and a lot more tech. Yet it still sits comfortably in the hand, is compact like a SLR film camera, and it is not all that noticeable when photographing in the street.
At the moment my current menu set-up is rudimentary. I wanted to starting walking around using the camera at the Adelaide Central Market then at Kings Head in the late afternoon to see if I could use it as if it were a manual rangefinder. That is how I used the Sony NEX-7. I could do it.
However, the A7r111's menu system is complex as this is a technologically advanced camera, and my rudimentary approach means that I won't be using the full capability of the camera. I won't be using the video as I do not have the software to process the video.
At the moment I am more interested in both the A7r111's image quality and its dynamic range for still photography. What really attracted me was the camera's low light capability. I needed that for the early morning poodlewalks, and it was that capability was what was missing from the NEX-7. I can now make photographs handheld before sunrise with the Sony A7r111. I can see the differences in image quality between the APS-C sensory the NEX-7 and that of the Sony A7r111. So there is no buyer's remorse.
My judgement is that the full frame mirrorless cameras represent 21st technology, whilst the DSLR style camera is a SLR that belongs to a different era, namely the film era. Using those camera body designs (the complex mirror box with a flipping mirror, groundglass and a heavy glass prism) for digital sensors is a stop gap measure to buy more time until EVF could be perfected. As mirrorless technology continues to improve there are diminishing sales and profits for the DSLR camera manufactures.
I reckon that Nikon's superb D850 is for people committed to, and invested in, the Nikon's SLR infrastructure, in particular the Nikkor lenses. Once you buy into a system--eg., Cannon or Nikon--you tend become locked in, as it is very expensive to shift camera systems. Many people have thousands upon thousands of dollars invested in those DSLR systems. Presumably, Cannon and Nikon will slowly make the shift to mirrorless over the next few years. The beauty of the Sony E-mount, however, is that it is an open standard: you can use these mirrorless cameras with the old lenses from other systems when coupled with a suitable adaptor.