PPRuNe Forums - View Single Post - Cockpit Video Camera
View Single Post
Old 18th May 2009 | 00:52
  #6 (permalink)  
Mark1234
 
Joined: May 2006
Posts: 779
Likes: 0
From: Londonish
Bit of a techie post, however, you may also want to consider the sensor type:

Most / many camcorders are a CMOS sensor. For this sort of application, a CCD sensor is 'better'. Each has pros and cons, but due to some esoteric features of the way the chip technology works, CMOS chips use a rolling shutter, whereas CCDs use a global shutter.

Golbal shutter is what you might expect - the entire chip is captured at once, every pixel comes from the same instant in time. With a rolling shutter, the chip is scanned a row at a time - One end of the image will be significant fractions of a second older than the other.

What that means is that when there's motion, such as vibration, or rapidly passing prop blades, you get artefacts in the image: The venitian blind effect where the prop should be, motion skew, or in extreme cases a sine-wave effect where the whole image is wobbling like jelly. A google search for rolling shutter should throw up some examples.
Mark1234 is offline  
Reply