>>>>https://www.youtube.com/watch?v=yr3ngmRuGUc
>>>
>>>Mm. I thought shutter speed applies only to still pictures.
>>
>>Riiight - but a video is just a bunch of still pictures. If the shutter speed and the helicopter blades are going at the same speed then you end up with a video like this one.
>
>I think Al explained it correctly.

Yep.

yr3ngmRuGUc