It's a Tawny Frogmouth. Southern Boobooks are brown (Frogmouths are grey), Frogmouths have very light colouring on the front, wing pattern is different (a good example of wing pattern of a Boobook and Frogmouth respectively would be these: Ninox boobook (Southern Boobook) on 3 Apr 2018 & Podargus strigoides (Tawny Frogmouth) on 15 Dec 2018) and Frogmouths have a distinct posture and shape (eg. head, perching posture at night). After you see a lot of them, you'll be able to recognise Frogmouths without having to compare them to other species - they're quite unique. :)
Sorry i should have been more specific. I have both Boobooks and Frog mouths in the park near me and even though Boobooks are brown in the night light they look grey and have a similar stance..
Frogmouths have a distinct patterning of white on their feathers with the most noticeable one on the edge of the primary flight feathers. I have added another photo which I edited to have more light so it's easier to see the pattern and colour. I also had another observer with me who agrees this was a Frogmouth. This is most definitely a Tawny Frogmouth.