> On Jun 6, 2011, at 9:52 AM, Paul Stenquist wrote: > > You can't just shoot at infinity or any other fixed focus setting and expect > to get good results. Subjects that are in the range of DOF will be somewhat > sharp, but not critically. You're probably getting some motion blur at that > speed as well. > > For shooting sports, go to a smaller stop, perhaps 5.6, and a higher shutter > speed, 1/500th or more, and focus on the target. With the *istDS, you'll > probably have to focus manually to nail it.
Thanks to everyone for the usual PDML generous, intelligent, and kind responses to my novice-y predicament. As Paul's first sentence makes clear, I was sorely confused on this topic, and have a lot yet to learn. Some observations in response, to test how much I understand: * Motion blur was not the problem. There was some of it in some of the images, but the I was talking about was the one you guys nailed: wildly inappropriate focus. *I have two choices: Focus manually on the target or use hyperfocal focus. [Though really, in the circumstances I described, focusing on the target is likely to be necessary.] * Hyperfocal focus: Use the DOF scale; set focus of the most distant point of the scale for the aperture used to the farthest point you want to be in focus. * On all lenses I've seen, there's a dramatic jump from the longest definite distance on the DOF scale to infinity. That's why it's often hard to set the hyperfocal distance. * The DOF scale is not the only guide to the hyperfocal distance. It can be calculated. There are tables. * Why is hyperfocal focusing called hyperfocal? * In the circumstances I described, use higher ISO [400 to 800], and faster shutter speed [1/500]. * Manual focusing in sports photography is difficult. It takes practice. One strategy is to focus on a location and wait for the action to appear. [Difficult in soccer. The goal mouth comes to mind, but it covers a lot more territory than a base in baseball.] * I've chosen manual focus because it forces me to learn. When I've learned, and it seems to be needed, I'll consider autofocus. At this point, that time is a long way off. That's what I'm taking away from what I got. Corrections of understandings and reminders of oversights are welcome. [*I* think my understanding is pretty vague.] Again, thanks to everyone who responded. I quoted Paul because he summed it up pretty well, but there was such clear near unanimity that I couldn't really single out any responses as most helpful. I do want to thank Matthew, though, for the link to the DOFmaster site. Sincerely, ------------------------------------------------------------------------------------------ Eric Weir Decatur, GA USA [email protected] -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
