Fn1	Allow for burst mode for Bracketing when camera set to singe shot.
	Fn2	Info Display off
	Fn3	Press to recall stored settings to take picture(s). Press again to revert to normal settings.
	ISO	ISO - Same as normal ISO
	PreV	Preview (not used?)
	Cycle	Cycle through AF modes
	Fn4	Go to My Menu
	mic	1 step Speed / Aperture change
	Focus ring	Change ISO setting
	Joystick	Reset focus to centre screen
	OK	Zoom to limit for composing only. Image will be at full view not Zoomed.
	WB	Modify White balance

To set a longer delay before power down on a Nikon Z9:

Go to the Custom Settings menu.
Select option C3: Power Off Delay.
Choose from four settings: Playback, Menus, Picture review, and Standby timer.
For each setting, you can select a longer delay time:
Playback: Up to 10 minutes
Menus: Up to 10 minutes
Picture review: Up to 10 minutes
Standby timer: Up to 30 minutes, or select "No limit" for continuous operation

Set up Recall Shooting Functions (Hold) in the following menu:

Go to the Custom Settings Menu (pencil icon).
Navigate to f2: Custom Controls (Shooting).
Select the button you want to assign the function to (e.g., DISP, sub-selector, video-record button, or any of the Fn buttons).
Choose "Recall shooting functions (hold)" from the list of options.
Once you've selected "Recall shooting functions (hold)," you can customize which settings you want to recall by pressing the right arrow key. This will allow you to select or deselect various camera settings that will be affected when you use the assigned button

Aperture priority mode can significantly impact low-light photography, offering both advantages and challenges:
Light control: In low-light situations, aperture priority allows you to set a wide aperture (low f-number) to let in more light. This can be crucial for achieving proper exposure without relying solely on high ISO or slow shutter speeds.
Depth of field: Wide apertures (e.g., f/1.4, f/1.8, f/2.8) not only allow lighter but also create a shallow depth of field, which can be desirable for isolating subjects in low-light portraits.
Shutter speed considerations: While aperture priority automatically adjusts shutter speed, in low light, this can lead to speeds too slow for handheld shooting, resulting in blurry images. To mitigate this, you can:
Set a minimum shutter speed in your camera's auto ISO settings.
Increase ISO to maintain faster shutter speeds, though this may introduce noise.
Creative control: Aperture priority gives you control over depth of field while the camera handles exposure, allowing you to focus on composition in challenging lighting conditions.
Lens limitations: In very low light, you may be forced to use the widest aperture your lens allows, which can limit creative options. Using a lens with a wider maximum aperture (lower f-number) can provide more flexibility in these situations.
Exposure compensation: In tricky lighting, you may need to use exposure compensation to fine-tune the camera's automatic settings and achieve the desired exposure.
By understanding these factors, you can effectively use aperture priority mode to balance exposure, depth of field, and image quality in low-light photography.
Recall settings (Hold) will not work if bracketing is set.