Why when you watch TV and you see a computer that bar goes accross the comp screen??

[NakaNaka]

I've always wondered that.

 

[kami]

Refresh rate/frame rate of the camera is different than the computer screen. In movies you won't usually see it because they either adjust the camera or the screen so both match.

 

[hypergeek]

ya it all depends on what you watching

 

[yakko]

<< Refresh rate/frame rate of the camera is different than the computer screen. In movies you won't usually see it because they either adjust the camera or the screen so both match. >>

That is why most times the computers are off on TV.

 

[BrunoPuntzJones]

yup, along time ago i thought it had something to do with bad power
i have a bud that owns a store and he has a camera setup to watch the counter, and there is a comp00ter there. he has the tv that shows what it is recording right next to it, and you can see the monitor shimmying away as said above, refresh rate.

 

[Bassyhead]

http://www.howstuffworks.com/question336.htm

 

[zsouthboy]

What happens is, the monitor is refreshing at 60+ times a second, and the camera is refreshing about 30 times a second.

The camera can't keep up with the image, and when it refreshes, It usually happens to be where the monitor is refreshing the line slightly below where it was before.

Hope that kinda makes sense.

zs

 

[zsouthboy]

This is why, though, that usually in movies the computers have LCD screens, with no visible refresh, so it doesn't have that bar thingie.

Many(if not most) news programs on TV are also using LCD screens for the same reason.

zs

 

[teriba]

It's the beat frequency between the camera's rate and the monitor's rate. Say they are 60Hz and 64Hz. You will have that bar moving at 4Hz. I win.