I wish I could show you what I'm talking about, but I have this weird crescent shaped artifact showing up in my upper left corner no matter what lens I use. My first DSLR, but I've been shooting for years on film. Its a Pentax K10D that has an automatic sensor shake to get dust off, but its not working. I'm about 99% sure that its dust, but I'd like to get somebody elses opinion on it. Can I post pictures on this thing? Anyway, does it sound like dust to you? Well it says attachments at the bottom, can I attach a photo to that? I'd give it a try I just don't want to screw anything up. Any help would be appreciated.