Radeon 9700 TV Output - Looks Horrible

  • Thread starter Thread starter croman44
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croman44

I have a Mitsu 65" WS TV and for the first time I tried to hook up my
desktop to the TV.

I have a Radeon 9700 and I used the S-Video connection for the hookup.

To be honest.. it looks absolutely horrible. To the point that it hurts
my eyes to try and use my PC that way. The wording is hard to read and
just plain painful.

Does anyone have any tips/tricks for doing this? I have heard others
say that they think it looks great on their TV but I am just not seeing
it.

Any help is appreciated

Thanks
 
Unfortunately that's limited by your TV. The NTSC standard calls for a
resolution of 720x540. That stretched over 65" just isn't gonna be pretty.
Text is going to be blurry and unreadable unless you increase the Windows
default font to size 96...

On the other hand, play a DVD or decent video clip on your desktop. It
should look great, perhaps better than your DVD player or satellite box.
It's just text that demands high picture definition.
 
The NTSC standard does not call for a resolution of 720x540.

In fact, the NTSC standard was adopted in 1952, and is purly analog.
There is no specified "resolution", there were no "pixels" when the NTSC
standard was adopted.

However, for what it's worth, the NTSC standard does use a 525-line scan
system (in the US) comprised of two fields, an even and an odd field, of
262.5 scan lines each (and yes, there really are half scan lines, and
you can actually see them on a good tv set with a vertical hold
control). However, about 20 lines are lost to the vertical blanking
interval (the black bar that you see if the pictures loses vertical hold
and starts "rolling"), so only a bit over 500 lines are available for
actual image display, and on real-world TV sets a number of these are
not visible on an actual TV set due to "overscanning". So while the
standard doesn't define "pixels" or resolution per se, from a vertical
standpoint the image has a viewable vertical resolution of about 480
pixels, interlaced into even and an odd fields of 240 viewable lines
each, from a total image component of 525 lines in two fields of 262.5
lines each.

Horizontally, the color subcarrier is at 3.58 MHz, so in "crude"
implementations, the monochrome bandwidth begins to fall off somewhere
around 3.2 MHz to make way for the color signal at 3.58 MHz and it's
sidebands extending upwards and downwards on either side of that
frequency. In fact, however, the color and monochrome information are
"interleaved", and sets with a high quality comb filter can extract
monochrme information up to about 4 MHz. A very, very rough rule of
thumb used by broadcast engineers is that you get about 80 lines of
horizontal resolution per MHz, give or take, and depending on the
quality of transmission and all of the equipment from signal generation
to the display CRT. So, for broadcast use, you can expect 240 to 320
lines of horizontal resolution, and it's tough to do much better than
that with a broadcast signal, limited by the color subcarrier, the sound
subcarrier and the nuances of vestigal-sideband AM modulation transmission.

However, if the chroma (color) and lumanence (monochrome) portions of
the signal can be kept separate -- truly separate, physically separate,
toally separate -- then there are no real limits on the monochome
resolution and it's possible to get up to 8 or even 10 MHz of monochrome
bandwidth, giving resolutions of up to between 640 and 800 lines. But
the only way to do that is to use S-Video connections between the
original signal source and the display (which may not be capable of
displaying that much resolution even if it is present).

Once the monochome and color signals are mixed, however (as they must be
in all broadcast and cable signals), the ability to achieve these higher
resolutions is lost forever, and no subsequent separation of chroma and
lumanence signals, or subsequent use of S-Video connections, will ever
restore them.
 
You need to use a digital interface (either DVI or HDMI (which is really
DVI with a different connector)). There is no way to even get close to
the necessary bandwidth for an image like a computer desktop with any
analog signal. You need 50 to 125 MHz of bandwidth, and no analog
connection provides more than 8 to 10 MHz (and many don't go above 4 to
5 MHz).

Also, if your 65" set uses CRT technology, there is no way for the
actual image generating components to produce an image that is sharp
enough (in terms of focus, convergence and geometric distortion) to
display what you think you want to see. This aspect of the situation
would be true even if you were using a digital (DVI or HDMI) interface.
Interface notwithstanding, you need a Plasma, LCD or DLP imaging
technology to produce an image with the resolution that displaying a PC
desktop requires.
 
Barry said:
The NTSC standard does not call for a resolution of 720x540.

In fact, the NTSC standard was adopted in 1952, and is purly analog.
There is no specified "resolution", there were no "pixels" when the
NTSC standard was adopted.
Click to expand...

[cut]

LOL! :D
 
BS82 said:
Barry said:
The NTSC standard does not call for a resolution of 720x540.

In fact, the NTSC standard was adopted in 1952, and is purly analog.
There is no specified "resolution", there were no "pixels" when the
NTSC standard was adopted.
Click to expand...

[cut]

LOL! :D
Click to expand...

OK. What part is LOL? That there were no 'pixels' in 1952? There
weren't. Barry refers to 240 to 320 lines of resolution. More
accurately, those are line PAIRS corresponding to 480 to 640 'pixels'
wide. The 601 standard defines 858 clocks per line of which 720 are
'active'. In the industry, this is 4:2:2 yielding a 27MHz data rate. of
13.5MHz Y samples and 6.75MHz each of R-Y and B-Y. And with sampling
comes 'pixels' but looking very closely at the original NTSC, while the
bandwidth is limited to 4.2MHz transmitted, a transition from level to
a new level can occur ANWHERE timewise within the active video area.
That means less jagged diagonal lines than is typically done with
computer graphics.

Other than that it is basically correct.

glenn gundlach
 
BS82 said:
Barry said:
The NTSC standard does not call for a resolution of 720x540.

In fact, the NTSC standard was adopted in 1952, and is purly
analog. There is no specified "resolution", there were no "pixels"
when the NTSC standard was adopted.
Click to expand...

[cut]

LOL! :D
Click to expand...

OK. What part is LOL? That there were no 'pixels' in 1952? There
weren't. Barry refers to 240 to 320 lines of resolution. More
accurately, those are line PAIRS corresponding to 480 to 640 'pixels'
wide. The 601 standard defines 858 clocks per line of which 720 are
'active'. In the industry, this is 4:2:2 yielding a 27MHz data rate.
of
13.5MHz Y samples and 6.75MHz each of R-Y and B-Y. And with sampling
comes 'pixels' but looking very closely at the original NTSC, while
the bandwidth is limited to 4.2MHz transmitted, a transition from
level to a new level can occur ANWHERE timewise within the active
video area. That means less jagged diagonal lines than is typically
done with computer graphics.

Other than that it is basically correct.

glenn gundlach
Click to expand...

quote!

the LOL is the story lesson about NTSC :D
 
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