Today I've just taken more out of focus shots of static objects with 5D mk ii than I've taken in 1.5 years with 40D. Thankfully most of the shots were ok.
It was snowing so I'm thinking that occasionally the camera focused on the falling snow and not my subject. Is this a commonly known problem? Quick googling and searching in this forum hints that I may have made the right conclusion but I didn't find anything totally convincing.
If this is the reason, any tricks how to improve auto focus performance when it is snowing?
In non-snowing conditions the camera hasn't had any auto focus problems. It's not the lens as this happened with 24-105 and 70-200 2.8 IS. I used center focus point as unfortunately the others are often quite useless. My 40D hasn't seen much falling snow so I can't compare to it.
I got out of focus on some very easy situations that I have never missed before. I checked shutter speeds/apertures/etc. and they are ok. E.g. a photo that contains only small balconies on a building wall (e.g. can focus only to balcony, wall or snow) using settings like f/8 + 1/100s + 95mm was totally out of focus. The next photo of the same subject is sharp with exactly same settings except double focal length.
I'll post examples later if there is reason to believe that it might be something else than the snow.
