I had a 4D at 28 weeks. They said it was the best time to do it. The baby would be well developed but not too big to get some great pics. I had my scan done at Exact Radiology for $100 which wasn't bulk billed. For that I got some coloured prints and a dvd of all the still shots. And it all depends on the day if your baby is wanting their photos taken. I was very lucky and got some very clear pictures.

Hope this helps.