It is possible that moisture and temperature change was largely responsible for the amount of moisture inside if cooling camera internals post-shooting caused it to draw in air and moisture through some of the weather sealed areas. This behavior is a good reason to keep the camera clean around the openings and controls because this is how salt/oil from your skin builds up and is then pulled into the camera along with any other contaminants on the camera body, especially in those areas surrounding the controls. Clean contaminant free water isn't great for electronics but mix in a little salt and then you will have real issues later.
Heat management is a tough issue with more sophisticated cameras, especially MILC with their greater power appetite which results in more heat to dissipate. My 1 series DSLR bodies use heat pipes to dump much of the heat to the battery compartment where it is conducted to atmosphere allowing them to remain highly sealed. I haven't looked closely at the R1 yet because I am not interested at this point in switching architecture but I would assume Canon has done some special tricks to keep it weather sealed while also rejecting heat to the outside.
Rick, you are a brave man shooting in the rain with a highly ventilated camera body 😂 I have a Canon XF-400 camcorder for video because I hate shooting video with a typical camera body but there is no way I would use this fan cooled ventilated little guy in the rain. I don't shoot much video and I consider the XF-400 a fair weather friend.
I have been shooting with Canon 1 series for a couple of decades (first with a 1D Mark II and currently with 1DX II and III bodies). I have shot sports in some pretty miserable weather and when I expect to be in nasty conditions the cameras and I dress appropriately.
I use Canon's combined lens/body covers which are awkward when using a multiple camera setup like I use but work well at keeping the camera body dry and moisture off the lens front element/filter.
But I have been caught by surprise a few times and have shot both soccer and football in heavy rain. The 1 series bodies and L lenses didn't complain and performed fine. I did dry them off before packing them away for the ride home but otherwise no special treatment.
Photos below are from a cold wet nighttime playoff game last fall. Forecast was for very light rain to move out of the area 2 hours before game time, the weather guy lied! The photos were below from a pair of unprotected 1DX III bodies using EF 70-200 and EF 400 f2.8 glass, the cameras did fine but we still had grass instead of turf last year so the photographer wasn't wearing cleats and I alternated between running and skating on the sidelines. Two of the officials had to have wraps applied due to slip and fall incidents during the game. It was incredibly messy.
Rodger
