Timelapse without in-camera support

Question

How can timelapse sequences be shot without having in-camera support for it? Which third party tools are recommended?

Answer

I have a Canon TC80N3, which works as a remote shutter, can do hundred of exposures at a timed interval (aka time lapse), a long delay before taking a shot, and very long exposures (ie, greater than 30 seconds that the camera can do).

They seem to be quite difficult to get new nowadays - but they do have them on eBay.

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