I've mentioned a couple of times before about how a camera in an underwater housing can become unusable well before the depth rating of the housing has been reached.

Well two weeks ago I took the opportunity to run a little test at work before a trip up the coast a couple of days later. I wanted to check the main o-ring, as it had more of an oblong rather than circular cross section. At work I have access to a pressure vessel. I took the housing for a Canon Ixus 870, rated for 40m, down to 60m for 5 minutes. The housing didn't leak at all, but I do know that springs in the housing go soft on a real dive after 25m.

So all I need to do is increase the spring power, by means of; replacement, stretching or spacers, and I'm almost assured to have a camera and housing that will work adequately past 50m.

Good work!

I can wait to see the results.

I can confirm that no case is required for either a 7D or a 500D at down to -10 for several hours and/or in light snow. But at less than 33% battery in such temps, AF ceases to function.

Any Pentax owners here care to do some real testing, for real men?! (mentioning no names of course)