Focus Mystery

[hughes]

Would somebody please explain why the front fender on this car is out of focus while the rear fender is relatively

sharp, aperture was F13 on a 180mm lens shutter speed was about 180th I think, on a Nikon D200 camera, for

some reason the EXIF data did not save the shutter speed. It looks to me like it is a focus issue not movement but

surely at F13 both the front and rear should be in focus as the car is traversing the frame. I'm puzzled if the level of

sharpness on the front was as good as the rear the shot would be okay as it is it is marginal. Any input would be

appreciated

 

Steve<div></div>

[petemillis]

I'd say it's definitely movement as opposed to focus issue. You're panning and you're not perfectly perpendicular to the vehicle so the angular speed of your panning arc can't match the front and back of the vehicle simultaneously. I'd still say it is good though.

[robbie_robertson]

Agree with the previous reply, and I think the shot is reasonably OK too. Pick your shutter speed up to a minimum of 1/300th or higher for action shots and things will improve. As I take more shots of moving subjects with longer zoom lenses, I find myself using shutter priority at 1/750th and higher ISO if the lens requires it: I found that a bird's wing flapping at a slower shutter speed will always look out of focus at the wingtips, which is simply movement blur.

[rnt]

After looking closely at the shadow of the right front tire where it intersects the ground I'd say that the front end was bouncing at the moment the picture was taken. Take a close look at the blur and see if it's horizontal or vertical. I'd bet it's vertical.

[hughes]

You guys are brilliant ! thank you. On a larger size print this is much more noticeable by the way, After close

inspection it is movement, I did not take in to account the upward/downward movement of the car, the front

suspension will be more mobile than the rear of course, I think the slow shutter speed was pushing the envelope but

when it works it works great.

 

Steve<div></div>