I would recommend anything from Central Australia and points North at that time of year, Brisbane and points North if you're thinking of the East Coast. It's the most comfortable time of year to be travelling in that area. South of there will be wintry and cold. Then again, because you'll be comfortable, the pictures you get won't be of spectacular waterfalls (dry season) or dramatic weather. Your choice.
PS: August is just the end of Winter in Australia and the weather is getting just a hint of the Spring instability at that time, so may be changeable at short notice.