I am currently in a cold country with temperature as low as -5 degrees celsius. This is my first time bringing out my XF8-16mm lens out for shooting and when I was out in the cold, I realised a fog/moisture building up at the centre of the front element (see 1st picture). I am bewildered because my understanding is that this should not happen when I transit from a warmer to colder environment. To get rid of the fog/moisture, I placed 3 packs of silica gel on top of the front element lens and close it with the lens cap - and after awhile the moisture/fog disappeared.
When I transit back to a warmer environment, my camera (x-pro 2) and the lens are kept inside a zip-lock bag with silica gels in it as well. However, this problem still resurfaces whenever I am out in the cold again. Is this a problem with the WR sealing?