This post popped up literally as I was proof reading the next CDG Newsletter; I was actually in the middle of an article by Christine herself on Cave Diving Videography. Talk about co-incidence!
Anyway, I hope she will not mind my mentioning that I think her article is extremely good and much of it would also be of use to anyone wanting to do still photography in sumps as well as shooting video. It'll be published at some stage in July ( in CDG Newsletter number 216).