I'm a little techno stupid here, but why does a TV or a computer monitor always have those bars rolling through it, like when an old TV has the vertical hold out of wack., when you take a video of it?
It has to do with the refresh rate of a TV or monitor. The picture on a TV or monitor is not really as it appears to us--it is actually the result of the very rapid movement of an electron beam (three for color displays) across the screen (vertical and horizontal). That is called deflection and it lights up the phosphors in the tube face. These have persistence and will stay lit for a while.
Our eyes see a complete image, while a camera sees a result closer to what is really happening.
The camera won't just see the moving line, because while its response time is faster than that of our eyes, it's nowhere near as fast as that electron beam is moving inside the picture tube. Instead, it will see a sort of combination--some of the picture AND a "flicker" or moving line.
The effect is less noticeable when a camera is pointed at a TV, because most TVs use an interlaced scanning method where all odd and then even lines are drawn, which gives less "flicker".
(The fact that the TV--at least for NTSC TV in the US--is running at a total frame rate close to what the camera is recording may also result in less apparent flicker or scanning in the recorded video.)
Computer monitors are typically scanned in a progressive, or non-interlaced method, where each picture line is drawn one right after the other, to the bottom of the screen. And the refresh rate is much higher than that of nearly any TV standard--usually at least 75Hz (times per second) vertical.
Thanks Bill, I'm 42 and was just shown that if I press this blue fn button and this other button I can make the screen brighter so I can see it better. I guess my wife was right, I can chain 44,000 pounds of machinery down and go screaming off the side of a mountain at 70 mph and it doesn't faze me but the little things in life still amaze me sometimes. LOL
phosphors...is this the gas in the TV tube like a flurescent bulb and when you charge it with electricity the molucels get excited and start moving around rela quick and start crashes into each other and put off light ??
There's no gas in a conventional picture tube. It's a vacuum in there, with a "getter" that soaks up gasses that were not removed when the vacuum was pulled.
The phosphors are actually light emitting material painted on a thin metal screen at the inner front of the tube. When the electron beam strikes a phosphor it is excited and glows as a result. Do this fast enough with the beam, and you get the apperance of a full picture.
I didn't know that software could do that! I have the old X10 stuff before they ruined the name. Mine is all IBM branded. I use to use it for my home theatre to adjust lights. It also came in handy for christmas lights. One command turns it all on, another off.
I have some of the IBM branded stuff as well. IBM had their own branded version of the X10 control software that they called "Home Director". I think it was actually sold as an option with some Aptiva computer systems.
It's a standard that came about sometime in the mid-70s. The X-10 of today and X-10 Limited appear to be much more closely related than the Wikipedia article on them would suggest. However, they have gone from a producer and developer of technology to marketers with highly questionable ethics and more focus on the sizzle than the steak. Hence the way I referred to them in the video.
I'm a little techno stupid here, but why does a TV or a computer monitor always have those bars rolling through it, like when an old TV has the vertical hold out of wack., when you take a video of it?
StarCar98 2 years ago
It has to do with the refresh rate of a TV or monitor. The picture on a TV or monitor is not really as it appears to us--it is actually the result of the very rapid movement of an electron beam (three for color displays) across the screen (vertical and horizontal). That is called deflection and it lights up the phosphors in the tube face. These have persistence and will stay lit for a while.
Our eyes see a complete image, while a camera sees a result closer to what is really happening.
uxwbill 2 years ago
The camera won't just see the moving line, because while its response time is faster than that of our eyes, it's nowhere near as fast as that electron beam is moving inside the picture tube. Instead, it will see a sort of combination--some of the picture AND a "flicker" or moving line.
The effect is less noticeable when a camera is pointed at a TV, because most TVs use an interlaced scanning method where all odd and then even lines are drawn, which gives less "flicker".
uxwbill 2 years ago
(The fact that the TV--at least for NTSC TV in the US--is running at a total frame rate close to what the camera is recording may also result in less apparent flicker or scanning in the recorded video.)
Computer monitors are typically scanned in a progressive, or non-interlaced method, where each picture line is drawn one right after the other, to the bottom of the screen. And the refresh rate is much higher than that of nearly any TV standard--usually at least 75Hz (times per second) vertical.
uxwbill 2 years ago
Thanks Bill, I'm 42 and was just shown that if I press this blue fn button and this other button I can make the screen brighter so I can see it better. I guess my wife was right, I can chain 44,000 pounds of machinery down and go screaming off the side of a mountain at 70 mph and it doesn't faze me but the little things in life still amaze me sometimes. LOL
StarCar98 2 years ago
phosphors...is this the gas in the TV tube like a flurescent bulb and when you charge it with electricity the molucels get excited and start moving around rela quick and start crashes into each other and put off light ??
StarCar98 2 years ago
There's no gas in a conventional picture tube. It's a vacuum in there, with a "getter" that soaks up gasses that were not removed when the vacuum was pulled.
The phosphors are actually light emitting material painted on a thin metal screen at the inner front of the tube. When the electron beam strikes a phosphor it is excited and glows as a result. Do this fast enough with the beam, and you get the apperance of a full picture.
uxwbill 2 years ago
I didn't know that software could do that! I have the old X10 stuff before they ruined the name. Mine is all IBM branded. I use to use it for my home theatre to adjust lights. It also came in handy for christmas lights. One command turns it all on, another off.
moldymac 2 years ago
I have some of the IBM branded stuff as well. IBM had their own branded version of the X10 control software that they called "Home Director". I think it was actually sold as an option with some Aptiva computer systems.
uxwbill 2 years ago
you guys always seem to make me laugh!
86cutlassSX1 2 years ago
Did you have lots of trick or treaters tonight?
mgospeed31 2 years ago
Yes we did.
uxwbill 2 years ago
Great!! If you got a CD or casette of spooky sounds it would be even better!!!
MrMoterKid 2 years ago
Radio Shack still sells that shit, I bought some if it, but I didn't know that it had been out for so long.
Sansui350A 2 years ago
It's a standard that came about sometime in the mid-70s. The X-10 of today and X-10 Limited appear to be much more closely related than the Wikipedia article on them would suggest. However, they have gone from a producer and developer of technology to marketers with highly questionable ethics and more focus on the sizzle than the steak. Hence the way I referred to them in the video.
uxwbill 2 years ago
I'm fond of your creativity here.
Ajaces 2 years ago
Expanding Operation Panopticon I see.
Been a long time since I've seen Windows 3.1 In action.
weasel2htm 2 years ago
5 days till Halloween already? 13 already and i'm getting old!
Segadude3000 2 years ago
HEY BILL HOPE YOU HAD A GREAT WEEKEND
howdy0473 2 years ago
I'm not terribly keen on heights.
(i'd love to pay a visit to the RP sometime!)
poopskinTheLiar 2 years ago
Don't worry...I'm not keen on heights either.
mgospeed31 2 years ago