You may need to wait a few years before you can get a camera that can take those shots, by overexposing by that much you are lighting the inside of your camera like a Christmas Tree and all bets are off for quality. The current crop of cameras can only handle 13-14EV. The Finepix S5 Pro could do that 10 years ago so sensor technology has not improved much for dynamic range but as we all know it has in other areas.
The cross hatch pattern are demosaic patters resulting from missing recognizable color information - you get similar patterns at very high ISO and it ain't pretty close up but not directly visible by the time you have something print worthy or downsize for computer and tablet screens.
If the shots were actually "keepers" there is still a lot you do to recover in post. I have attached my take on it ( I had to compress a little to get the size down).
The Trees: I ran max Highlight Recovery and tight Curves on one, Knocked out Magenta and Purple on one, and show the original for the sake of the Histogram and Blow-Out warning.
Edited by asathor, 27 December 2016 - 06:07 AM.