Tor:
Tx for the clarification. What you're referring to is called "Visual Circling" in Australia when coming off a non-precision approach. Criteria:
1) "After initial visual contact, the basic assumption is that the runway environment (i.e., the runway threshold or approach lighting aids or other markings identifiable with the runway) will be kept in sight while at MDA for circling." - JEPP Terminal AU-20
In other words, pilots discretion on VIZ.
In regards to precision approaches, Australia only has ILS facilities to CAT I standard (this is paradise - we don't get bad wx!). Therefore min flight VIZ at the minima are those published on the chart (location specific) except that:
1) VIZ 1500m required when High Intensity Approach Lighting is not available
2) VIZ 1200m required unless:
a) Aircraft flown to minima manually using Flight Director or is autocoupled
b) Aircraft equipped with serviceable failure warning system for the primary ATT & HDG reference systems AND
3) High Intensity Runway Edge Lighting is available.
A Visual Approach is, for us, a way of choosing our own altitude while on a specified track (until within a certain area) in VMC while still under positive control.