I took my AF dead 500mm f4 AFS lens on my D850 for a walk around the local nature reserve over the weekend. Using Focus Peaking on the backscreen was doable for things like ducks in the middle of a lake where it was easy to 'see' the focal plane move to and fro with slight focus ring rotation. Stationary small birds in bushes were OK for similar reasons. I decided to have RED as my 'in focus' indicator colour. However, I then tried (for fun) my Sigma 60-600mm f6.3 set to MF. Sure the indicators were there but there seemed to be far fewer red bits.... and some twigs and things never went red at-all. So, what decision/info does the camera make to highlight certain bits? High micro-contrast areas? Is it aperture related, ie does the mechanism need lots of light? I had a look in the manual (I know crazy or what?) and the bit about Focus Peaking LEVELs says.. The options in the Peaking level menu are 3 (high sensitivity), 2 (standard), 1 (low sensitivity), and Off; the higher the setting, the greater the depth shown as being in focus. I'm obviously reading it wrong but that sounds kinda backwards. I take it Low Sensitivity is the most precise? Does this work the same way in a mirrorless EVF? The ergonomics of using focus peaking on the back screen of the D850 is very far from comfortable.... and I'm tempted by the new MK ii versions for this very use, and video. Has anyone got both the D850 and Z6/7ii? and can do a quick evaluative test. There are a few review type things available on-line but I trust the members here not to be biased... Late Edit. Why didn't/doesn't the D500 have Focus Peaking?