Inconsistency using A-priority

[Shutter_to_think]

Okay, I'm just trying to get my brain around getting consistent shots in Ap mode shooting baseball. Here's the problem:
I get really great shots from a certain angle shooting the hitter at home plate, he hits the ball, I track him all the way to first base. All the photos at home are perfect and then slowly get brighter as he gets to first base. By the time he's there, the pictures are worthless. Blown out and just absolute junk. What the heck am I doing wrong? I'm focusing on the runner the whole time, my focus points don't change.
BTW, I am using Nikon D700.
Any help is appreciated.

[Richard]

What metering mode are you using?

[time2smile]

First welcome, dont know the settings in the D700, but it sounds like your exposure is locking with the shutter half pressed.

[pathfinder]

how about the exposure data from a series of images, along with a couple examples of the images, too?

[mercphoto]

First welcome, dont know the settings in the D700, but it sounds like your exposure is locking with the shutter half pressed.

The easiest way to tell is to see if the shutter speed varies any during that blast of shots. I suspect it is not, and that is why the exposure is off.

[Harryb]

I have had the same issue with wildlife captures. My problem was my EV setting. The subject would move from subudued light into brighter light and I failed to adjust the EV setting as it moved onto the brighter light. You an set up your controls so that the rear control wheel will adjust your EV setting so you can adjust it on the fly w/o taking your eye from the viewfinder.

[Shutter_to_think]

Thanks all. I will upload some pics when I get home from work.
The shutter speed may be changing I'll check, but how in the world can you change your EV on the fly? And it also didn't matter if I tracked the runner. Even if I stopped shooting and recomposed, it still did it.

[pathfinder]

If the later pictures are over exposed, it sounds like the light is brighter as the runner progresses, and the exposure is not being altered from the first exposure. That is why I want to see exposure data and images to see what is going on.

[Shutter_to_think]

I'm still at work, but will post soon.
Here's my quandary. Shouldn't the camera adjust to aperture/shutter. I could see if I was shooting into more light, then I expect the shutter speed to be higher so the pictures are consistent. So, I hope the shutter speed changed.
I could see if I was shooting manual and had this problem, but the camera should be smart enough to adjust.

[mercphoto]

I'm still at work, but will post soon.
Here's my quandary. Shouldn't the camera adjust to aperture/shutter. I could see if I was shooting into more light, then I expect the shutter speed to be higher so the pictures are consistent. So, I hope the shutter speed changed.
I could see if I was shooting manual and had this problem, but the camera should be smart enough to adjust.

You're assuming that inbetween shots in a burts (i.e. shutter held down constantly) that the camera will re-calculate the exposure. Typically only the high end cameras will do so. I do not know if yours will. I would expect a Canon 1-series to do this. I would not expect a Canon 40D to do so.

[Shutter_to_think]

Maybe that is where I'm getting confused.
I am off in 3 hours and will post pics with exif.
Thanks so much everyone for the help.