Micro adjustment follies

I bought a used 100-400L this past week in the hopes of trading out my 300/4L for the zoom. The lens came Friday and I had a very short window of daylight when I got home from work to take a few test shots with the 100-400 and my 300L.

I was a little bummed to see that while the 100-400 was super sharp at f/8 it seemed to be a little soft at f/5.6. It was certainly softer than my 300/4L with both wide open.

Today I decided to check the MA and see if the focus was off a bit. I set up a test and lo! - the lens was front focussing just a hair.

So I went to the menu on the 1D Mark III to correct this and found out that the MA for the 100-400 was already set to -3. I bought my 1D3 used and apparently the previous owner had a 100-400L. It was a funny head slap of a moment.

Remember to check that there is no MA set for your lenses if you buy a used body.

Haha.

Yes, I can see how that would confuse the heck out of you. I'm sure there's been many people bought second-hand cameras only to find out that the focusing doesn't work (it's usually because people have put the focus on to the * button).