I've got a Nikon with a data back that can be set to take pics at certain intervals, it's a 35mm. 35's also have the option of cable releases, it's simply a cable with a remote shutter release. I'm not sure that you'll find that on a digital however. There's also a kits available for mine that offers an electronic remote. I know you don't want a 3rd party but I wouldn't peek much. LOL

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