Propellers and cameras

[Frank]

A very good explanation of why some cameras do disgusting things with your propeller.

http://phys.org/news/2012-05-hall-ef...ts-mobile.html

Frank
(the guy blinking over there in the corner)

[Charles]

Yep, rolling shutter.

The other thing with cameras like the iPhone, and even GoPro, is that exposure is automatically controlled by setting the shutter speed. (Not the frame rate, but the amount of time the shutter is open for each frame.) So on a bright day the shutter speed is very fast and it 'stops' the prop. A solution to this is to use a neutral density filter and get the shutter speed much slower, down to something like a normal video camera uses (~1/60 sec), and the prop will blur and you won't see it in the video.

[Pilawt]

Here's a video by Phil Boyer explaining the problem and how to deal with it: http://swainhart.org/2011/how-to-fix...er-distortion/

This guy is selling a modified GoPro case with built-in filter: http://www.thepilotreport.com/stop-g...r-artifacting/