Problem with Canon Eos 450D

I wonder if anybody can help. Last night I noticed what I suspect to be a problem with my Canon 450d:

When previewing images on the camera, I click the display button to take me through to the smaller veersion of the image preview (the bit which gives you the details of the settings you used to take the photo) and on some but not all pictures, small black blotches flash in the lighter bits of the pictures. Does this happen to anybody else and is it a problem worth persuing? It doesn't happen when I preview the images in full screen mode.

Regards,

Matt

Are the black blotches only flashing on the very bright patches?

If so, this is a feature, showing you what areas of your photo that you have over-exposed. I believe you can turn this off somewhere in the settings (check your manual), but I found it very useful when first shooting as it showed me if I'd screwed up a shot, and then I could just re-take it.

I rarely see it now that I've learned how to properly expose shots, but I still leave it on just in case I screw something up

Yup its normal. you can turn it off in settings I think

Thats music to my ears- thank you very much guys

Matt

Arrgh, don't turn it off, this is a really useful feature! It's better to know which parts of the image are over-exposed so you can retake the shot with slightly less exposure. If you lose the highlights you can't get them back in post processing.