I found this video from a Czech Mi-35 Hind (the exact vehicle is construction number c/n 203369 seen at 0:36) showing a neat nice trick achieved by synchronizing the video capture frame rate with the blade frequency. The video here.
Seen formerly on http://view.break.com/295948
Image: Not the same but one from the same batch and air force from ajmotors (CC BY-NC-SA 2.5).
