thebowtie said:
What we want is 'Hydrophilic' - water-repelling.
Correct term - as used by the BBC in the above program, which I watched with interest, too - is
hydrophobic ('tending to repel or fail to mix with water'). This is actually the exact opposite of 'hydrophilic' (lit. 'brother to water'). And by the way: anything with 'hygro' relates to
all moisture rather than just to water.
It also requires careful engineering so that all potential points of water ingress (think buttons, switches, displays, battery-compartment, CF-card case, electronic interface points (HDMI, USB, N3, X-Sync, etc.) are also made to resist water ingress.
The hydrophobic coating that the BBC demo'ed could be applied to
all surfaces, including those internally in the camera. Such a through-and-through seal, as shown by Miracles of Nature, would
not require seals as you describe 'em, it would just make
everything water-repellent. This would be done by toying with surface tension on a molecular scale, is what I understood from it.
The difficulty with that solution is electric currents. The smallest scratch in such a coating, e.g. on the contacts of a memory card or in a switch, which tend to be vulnerable to scratches anyway - and the conductivity of water would render your device useless. A phone without an sd-slot, without mechanical switches, with a soldered-in battery and with a properly sealed sim-card slot might be commercially waterproofed using hydrophobic coatings. For electromechanical devices such as dslr's, current solutions are regrettably as pricey and cumbersome as they are optimal, if you ask me.
Mind you, I'm talking about fully waterproofing a camera here. Obviously such a coating could go a long way in making a camera more water-repellant.