Have never any issues with the boat electronics, but probably because I wasn't in "Extreme" temps.
Years ago when I was using cameras out doors in Very cold temps (like 20+ and on down to -20 or so) I would put a desiccant into a plastic baggie with the camera, seal it and then put it into the equipment bag. Usually with the lens on. Then they would come into the heated environment and wait in the equipment bags for 24 hours before getting opened. No moisture issues with them then.
I'm a firm believer in mild to moderate temp changes for electronics, especially if you are going through the freeze zone (32F).
Harvey
SleepyC :moon
Years ago when I was using cameras out doors in Very cold temps (like 20+ and on down to -20 or so) I would put a desiccant into a plastic baggie with the camera, seal it and then put it into the equipment bag. Usually with the lens on. Then they would come into the heated environment and wait in the equipment bags for 24 hours before getting opened. No moisture issues with them then.
I'm a firm believer in mild to moderate temp changes for electronics, especially if you are going through the freeze zone (32F).
Harvey
SleepyC :moon