Well we did another try yesterday evening. Pink and white were the colors.
I had a 3 by 4.5 m black cloth as background. Fixed with weight at the border of the swimming pool and at bottom. Well, I used a 15mm lens to be reasonably close to the model because of the dust and dirt in our swimming pool. Framing the model (with floating clothes) became somewhat of an issue. I had to get very close and the there is of course the barrel effect...
Furthermore Evelyne has problems with her buoyancy. Hence we forced to have a weight belt or weights around the ankles. Based upon the feedback on this website, we tried to get some more floating clothes. It did work very well because the problems mentioned above. But it was a good learning experience.
Lesson learned:
1) I'm going to enlarge to black cloth to 4.5 and 4.5 meters.
2) I'll use my 18-70mm lens next time.
This one is my favorite of this shoot...