Canon f 1.8 VS f 1.4 for HS BB

[dsgreen3]

Newbie taking photos of high school basketball. I have a sigma 70-200 mm lens f 2.8 and would like something for under the basket with about only three feet to the wall. Again very new to photography and have an oppertunity to buy older metal mount f 1.8 or newer f 1.4 which would work best for me on a Canon 40D body.
Thanks

[inkista]

We're talking 50mm, right? f/1.4. It has USM, which will make it faster on the autofocus.

[dsgreen3]

Yes were talking 50 mm, What about the old metal mount f 1.8 50 mm how's the auto focus on that lens? Would there be any issues with a novice taking photos with the f 1.4 50 mm lens.

[inkista]

Both versions of the 50/1.8 do not have USM. You get the Mark I with the metal mount for build quality and for manual focus usage (distance scale, better MF ring), but optics are identical to the 50/1.8 II. Most people go for the f/1.8 simply because of cost.

The main issues you'll have as a tyro with the 50/1.4 are going to be related to shooting with a fast lens wide-open to get more light. Large apertures have thin depth of field, which makes focusing accuracy much more critical. The thing to remember is that just because your lens cranks open to f/1.8 or f/1.4 doesn't necessarily mean you have to shoot with it set there. Stopping down to f/2 or f/4, while it will reduce your shutter speed or force you to up the ISO will increase your DoF, so focusing has a little more elbow room for error. You still need to be accurate, though. Read your manual and master your AF system and AF point selection.

[dsgreen3]

Thank you have been very helpful.