Hi Arfur,
When we went we took a videocamera and a digital camera.
Both worked fine, considering the low light levels and long periods of darkness, but they do warn you that all types of cameras may malfunction at such low temps and are therefore you can't claim for them on insurance.
Clothes wise - under the snowsuits we had:
Usual underwear; thermal vests and long johns (bought them brand new from ebay); thermal polo jumpers for the children (bought from the kidski website), ordinary tops for adults; then zip up fleeces (children's from kidski, ours from Primark!).
Gloves and hats essential. Children had the type with the side bits to keep their ears warm.
Scarves just got in the way a bit, we found.
Take lots of socks - then wear one pair of ordinary and one pair of thermal over the top.
We managed with two sets of thermals each, and one jumper and fleece each as there was a drying room in our apartment.
Hope that helps.
Have fun - you'll love it!