first set the focus to manual:
then hit the 'ptz' button on the upper right of the 'live view' to show the PTZ settings:
use the controls above to put the cam where you want it, zoom, & focus.
select a preset and click 'set' to save it, 'call' to go to a previously saved preset.
(you might need to scroll that pane to see the 'set' button right of the 'call' button
for each preset)
There doesn't seem to be any OSD for focus changes, so you kind of just need to keep
track of where you're at and what you've tried (focus far vs near), but they do
seem to get saved and recalled with the presets. I set my field of view and focus
for daytime in preset 1, 'clone' it to preset 2 (call 1, set 2) then change focus only
in preset 2 for nighttime and 'set' that.