Hi guys, we had a 4d done at 24 weeks as my Mum was staying with us but felt that 32 and 36 weeks showed a lot more detail - just in case anyone was wondering whens the best time to have them done, our week 36 showed really good facial features that you could hold up to our baby pics pics and see the resemblance - cant wait til she arrives and can compare also...they are priceless and amazing what technology can do now...