Foo - Digital camera problems. Since y'all are awesome photogs, maybe you can help.

30D, about 6 years old.

Suddenly, it's overexposing everything.
I have to shoot full manual - the little meter at the bottom overestimates light severely. For example, it's at 0, when it's really +2.

So in any kind of automatic mode (such as Av) it overexposes like crazy.
I worried about my lens, but I bought a 5D MKII to test it out, and the lens is okay.

Has anyone run into this before?

Trying a firmware update...

id guess there is soem sensor that detects light and it was dirty .but thats my guess

Hmn, if it was dirty, it would certainly think there's a lot less light than there actually is. I'm not sure if the metering is done in the CCD or if it's another piece entirely. Though this is a "fine 1 shot bad the next" kind of deal.

Hmn, if it was dirty, it would certainly think there's a lot less light than there actually is. I'm not sure if the metering is done in the CCD or if it's another piece entirely. Though this is a "fine 1 shot bad the next" kind of deal.

My 30 D had some problems with the shutter release which affected all of the exposure functions. The easy fix is to drop some contact cleaner down in to to battery compartment with the camera upside down. Then blow it out with a can of air. Make sure the contact cleaner is not one that will melt plastic.

Also try resetting any custom functions.

Have you changed lenses by chance?

I owned a Nikon D70s and a Sigma 18-50 that worked real well. I bought a Nikon D300 body and the Sigma lens was not reliable with it. You could slowly zoom through the zoom range and watch the aperture jump by 1 or 2 EV at a consistent point in the middle of the zoom range. I had the lens contacts cleaned and that didn't help. I don't know if Canon lenses communicate with the body the same way but the body has to know what the aperture is for the lens so it can calculate exposure properly.

Another thing that could be an issue is the auto-aperture in the lens or maybe in the body. The lens probably has a pin that the body depresses to close the diaphragm during exposure but leave it open for focusing. If the body is moving the pin an inappropriate amount that could change the exposure significantly.

If your 30d is consistently exposing one way or the other you could simply set something like +2 or -2 and that should compensate for it.

I would recommend going to a bigger camera forum like the ones on dpreview.com and reearching your problem, maybe ask your question there.

Try a full reset. I have also heard that replacing the in camera clock battery helps correct some problems, but I've never done it.

'Y'all'?