Using regular TV as computer monitor?

cockroachfarm

cockroachfarm

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Jan 6, 2001
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I have a client who wants me to set up a computer at a trade show so he can play a product CD-ROM on the laptop and show it on a 42-inch flat-screen TV.

What do I have to purchase to make that possible?
 
Preferably you need a graphics card with a "TV-out" plug. Or there is probably an adaptor available (I know there are adaptors to do the opposite). Check NewEgg and TigerDirect - if there's any such thing, they'll have it.

Best Luck,
Bob
 
if he has a good laptop it will have an Svideo output or a D-Sub video out(regular monitor plug) Assuming the 42" is a plasma it "should" have a D-Sub input. You'd just need a monitor cable long enough, then setup the plasma as the second display in the windows display properties. This is how I watch movies at home, but using component output from my desktop to my TV.
 
Thanks for the info. I think what he is going to do is buy an inexpensive desktop system, hook it up to the TV as you folks suggested and then give the desktop system to some kid at the end of the show.
 
thats doable for like $300. just make sure the card you ahve will support the resolution of the TV and that the TV has the right connections.
 
the resolution wont be really good with a "regular tv" (crt) but lcd:s plasmas and similar high resolution tvs will work fine
 
Get a decent LCD TV with a VGA input so you can connect directly into the graphics card

If you hook it up via the TV out on a graphics card the resolution will be terrible
 
bladefixation2 said:
...Get a decent LCD TV with a VGA input so you can connect directly into the graphics card...
Click to expand...

I think that's what he's planning to do. But, another exhibitor is loaning him one of their 42-inch LCD screens and I have a feeling the quality of the picture will be so-so.
 
Gollnick said:
For a tradeshow, you want it to look good. So, the device you want is called a scaler/scan-converter.

Extron www.extron.com is a big name, though it's hard to buy their stuff. Kramer Electronics is a good one http://www.kramerelectronics.com. RGB Spectrum, http://www.rgb.com, is well-respected. There are others.
Click to expand...

I can vouch for Kramer Electronics. Their scan converters work great. We use the this model. We've also used several of their VGA video distribution amplifiers that work equally well.
 
works a whole lot better if the TV has a serial plug... just have to move my tower over my the tv and hook it right in.
 
OK, next step. :)

He bought a 42-inch plasma screen and tonight, for practice, we hooked it up to my laptop as an "external monitor". Played the CD-ROM and it works great...except for one problem: he wants the picture to cover the entire 42-inch screen. When we play the presentation (on the laptop screen or on the big screen) it covers only the CENTRE two-thirds of the screen. The outside edges of the screen are black. Is there a screen setting I have to adjust to make this presentation show up on the screen as large as possible (proportionately, of course)? Parts of this presentation include video/audio travel footage as well as VR clips of room interiors. Would cost have been a factor in NOT making it appear full-screen? When I tell him that I'm not a freakin' A/V technician, he just laughs and says, "I know. But you can figure out how to do this, right?" :rolleyes: :confused: :rolleyes: (Wrong.)
 
You have now discovered the "aperature ratio."

The human eye has a rectangular field of vision. It's aspect ration is about 1:2 which means that for every inch tall, it's about two wide. 1/2=0.50.

But, the extreme left and right are not in focus very well. The area of good vision is the center and has an aspect ratio of about 5:7 for every seven inches wide, five inches tall. This is why conventional photographs are 5:7 ratios, the 5x7 is a classic size. 5/7=0.71.

The problem with 5:7 is that it's fairly rectangular. CRT picture tubes are difficult to make rectangular. For best results, they should, in fact, be round. The closer you get to round, the better off. But, we don't want round pictures. The best you can do for a picture tube then becomes square which is an aspect ratio of 1:1. 1/1=1.

Ordinary TV is 4:3. This means that for every four inches wide the screen is, it's three high. This makes Most computer monitors (until recently) have been 4:3 too. Consider, for example, SVGA, 800x600. For every four pixels wide, it's three pixels high. This is not square, but it's not overly rectangualar either. 3/4=0.75. That's closer to 0.71 which is the ideal aspect ratio of the sweet spot in human vision, but it's still close enough to 1.00 that CRT tubes can be fabricated in this ratio.

Movie theaters use an aspect ratio of 16:9. For ever 16 feet wide, the screen is nine feet high. 9/16=0.56. They'll tell you that they do this in order to more closely match the aspect ratio of human vison which is 0.50. But, if this were truly their goal, then why stop 0.06 shy of the goal? Why not go to a true 1:2 ratio? Keep in mind that while human vison has a 1:2 ratio overall, the center where it's in focus is about 5:7. If the truth be known, the truth is that the reason theaters have migrated to 16:9 is so that they can fit more seats per row.

The new HDTV is uses an aspect ratio of 16:9. But, remember that old-fashioned TV is 4:3 and most computer video is 4:3 too. There are three ways to deal with this:

1) Fit-To-Screen. Just take that 4:3 image and stretch it to fit that 16:9 screen. But people are going to look fat. Circles will become ovals. This is not good... but it's still done.

2) Pan-and-Scan. This means to take a 16:9 ratio piece out of the 4:3 image and display only that piece. The piece is moved around to follow the action. But, sometimes there's action all over the screen. And, all of the time, you'll be loosing some of the picture. Furthermore, Pan-and-Scan is a manual process.

3) Letter Boxing. This is what you are experiencing.

Somewhere in your system there might be an option for "Fit-To-Screen, but it just won't look good.
 
Gollnick is right.

The only way to fill the screen is to shoot your presentation in the same aspect ratio of the display.

Either you will lose the top and bottom of the presentation or you will stretch it out and look ridiculus.
 
cockroachfarm said:
OK, next step. :)

He bought a 42-inch plasma screen and tonight, for practice, we hooked it up to my laptop as an "external monitor". Played the CD-ROM and it works great...except for one problem: he wants the picture to cover the entire 42-inch screen. When we play the presentation (on the laptop screen or on the big screen) it covers only the CENTRE two-thirds of the screen. The outside edges of the screen are black. Is there a screen setting I have to adjust to make this presentation show up on the screen as large as possible (proportionately, of course)? Parts of this presentation include video/audio travel footage as well as VR clips of room interiors. Would cost have been a factor in NOT making it appear full-screen? When I tell him that I'm not a freakin' A/V technician, he just laughs and says, "I know. But you can figure out how to do this, right?" :rolleyes: :confused: :rolleyes: (Wrong.)
Click to expand...

You have a 4/3 input signal and a 16/9 TV screen. The TV shold have a mode called "ZOOM" or whatever the manufaxturer feels like calling it. This mode crops out the top and bottom of the 4/3 image and "stretches" the reminder over the whome 16/9 screen. It's the best you can do in this situation, at least it's what I found best when I play the TV-out signal on my 16/9 screen. What model is that TV screen? Maybe they have a user manual on their web site...
 
Thanks for all the info and suggestions, folks! (Chuck - you're amazing.)

First thing I'll do is look for a screen "Zoom" feature on this TV. I'm fairly computer literate, but these new monitors and TVs have so many menus and sub-menus it's getting to be you need a pilot's licence to dig out some of these available features! :o

The TV is a 42-inch plasma made by a company called Prima. Outstanding value for the money!
 
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