There small items I noticed with my Z9.
I was using the Z9 with the 100-400 mm Z mount lens in Yellowstone last month (with and without the 1.4x Z TC). Great lens. I kept noticing that the aperture often changed to a smaller number. One time all the way to f45. I thought this was odd, as the front command dial (which I use for aperture when shooting manual with auto ISO) is not that easy to turn. I just discovered the problem. In my custom settings, F2, the lens dial was set to change aperture. I think this is a default setting, as I do not recall changing it. I turned this dial off, as it seems too easy to change unintentionally.
I have also been setting up the recall shooting function, applied to the lens button. This worked fine on the 100-400 and I set it for both lens buttons. But it was not working on my 500 mm PF. It turns out that you need to set the physical switch on the 500 mm PF lens barrel to AF-L in order for the lens button to be set by the camera custom settings. Brad Hill gently pointed this out to me when I said I could not get RSF to work with the lens buttons on the 500 mm PF. It is mentioned in the Nikon manual for the 500 mm PF, but is easy to miss.
Recall shooting functions will change AF areas, but not AF modes. So in a landscape bank set to AF-S and pinpoint, RSF would not allo;w me to change to AF-C and wide area in a single button press (for unexpected action). It did still change shutter speed and frame rate, leaving me with 1/3200, 20 fps, AF-S and pinpoint, an odd combination. I may go to AF-C and single point for my landscape bank if I want to use RSF.
I was using the Z9 with the 100-400 mm Z mount lens in Yellowstone last month (with and without the 1.4x Z TC). Great lens. I kept noticing that the aperture often changed to a smaller number. One time all the way to f45. I thought this was odd, as the front command dial (which I use for aperture when shooting manual with auto ISO) is not that easy to turn. I just discovered the problem. In my custom settings, F2, the lens dial was set to change aperture. I think this is a default setting, as I do not recall changing it. I turned this dial off, as it seems too easy to change unintentionally.
I have also been setting up the recall shooting function, applied to the lens button. This worked fine on the 100-400 and I set it for both lens buttons. But it was not working on my 500 mm PF. It turns out that you need to set the physical switch on the 500 mm PF lens barrel to AF-L in order for the lens button to be set by the camera custom settings. Brad Hill gently pointed this out to me when I said I could not get RSF to work with the lens buttons on the 500 mm PF. It is mentioned in the Nikon manual for the 500 mm PF, but is easy to miss.
Recall shooting functions will change AF areas, but not AF modes. So in a landscape bank set to AF-S and pinpoint, RSF would not allo;w me to change to AF-C and wide area in a single button press (for unexpected action). It did still change shutter speed and frame rate, leaving me with 1/3200, 20 fps, AF-S and pinpoint, an odd combination. I may go to AF-C and single point for my landscape bank if I want to use RSF.
i suppose there are people that never bump anything they don’t intend, but i’m not one of them 
