I have noticed that my 24-105 L exhibits some pretty severe purple fringing with high contrast situations especially at the long and short ends unless it is stepped down to 6.3 or higher. I am using it on a 50D and it is much more pronounced than any of my other lenses. Is this a common problem with this lens or do you think I need to send it in? I will try to post some examples tommorrow, but it is very evident.


