Helicon Soft Forum

I am testing Helicon remote (evaluation mode) for makro timelapse shooting.
Canon 550D, Sigma 105mm/2,8 Makro lens

I shot a watch 1:1, distance about 30cm, f 8, 1/4 exp time, ISO 200, focus stack with 5 pics. In the stacked pic the whole watch is in focus.
I combined this with the intervalometer function and took a 5 pics set every 60sec.
Everything connected fine and worked. However I encountered a very similar focus shift on all tests. It started fine on set 1-10, so the first 10 stacked pictures were beautiful and in focus. But then the focus shifted very slowly towards the camera. After about 30 sets, that is 30 min, all the pics were completely out of focus.
The frame didn´t change at all, so it can´t be the camera slowly sinking and the object also didn´t move. Unfortunately I don´t have another makro lens to test it with.Is it a problem of the lens or the software?

Any help, ideas appreciated.
Chris

Hello Chris,

The most probable explanation is that you're facing focus drift. Due to the way focus drive works in most lenses, every movement is a little bit shorter than it should be. So when you do many small moves, this error builds up very quickly.

thanks, that makes sense.