Shoot L glass wide open?

[jespdj]

<i>...is L glass good enough to shoot wide open?</i>

<p>It depends. Not all L lenses are equally good. I have two L lenses: the 17-40 f/4 L and the 200 f/2.8 L.

<p>The 200 f/2.8 L is amazing, the image quality is very good even at f/2.8; very sharp, very good contrast, very good colours.

<p>With the 17-40 f/4 L, it's better to stop down a bit, is my experience. At f/4 it is not incredibly sharp, especially in the corners, and I also get vignetting.

<p>I'm using those lenses on a 5D (full frame).

[ronaldo_r]

Using a fast lens wide open, it may be challenging to gain enough DOF on a moving subject, hence the "softness"...

[william_jennings]

Thank you all, I believe you have answered my question.