I picked up a 1D Mark IIN a few days ago, it's my first time with a 1-Series body. I'm moving from a 40D/60D set up to a 1D IIN/40D set up as I'm shooting mainly sports and events. The previous owner was a press photographer who used the camera for years and looked after it, she never had a problem with it.
I've noticed that there's a slight hesitation before it attempts to find focus and it's noticeably slower than my 40D, it doesn't feel quite as snappy. I've tested it on a Sigma 24-60mm F/2.8 and a Canon 70-200mm F/2.8L and the results are the same. The tests are using only the centre AF point. The 1D hunts a fair bit more in lower light than the 40D but I put that down to the age difference between the two. Could the hesitation problem due to the age as well? I wiped down the lens contacts but that didn't make a difference.
I'm considering sending it in to the local Canon service centre here in Dublin, but would just like some other opinions before I do so.