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harrisjamieh · Feb 11, 2006, 10:59 AM

My old Sony computer had a composite video out, which I used to connect up to my Sony 17" LCD TV. The quality was poor, and text had to be at about 16pt to be readable. My question is, if I buy the DVI>composite/S-Video adaptor, and use the S-Video to connect my video out on my iMac, will I see improved quality on my TV, and if so, to what extent?

Will C · Feb 11, 2006, 12:36 PM

Improved - compared to what?

At the risk of teaching you to suck eggs - it will be worse than what you see on you iMac display since the resolution of standard def TV is only 575ish (PAL) or 480ish (NTSC) visible lines compared to 900 or 1050 on the 17 and 20 inch iMacs so the output has to be scaled which also has compromises.
The other problem is that most CRT TVs use interlaced scanning and so it may to flicker particularly on small details. TV pictures which are 'designed' to be viewed from across the room rather than up close like a computer display.

Having said that, since the Intel iMacs can monitor span, I think if you set your external display to be a proper TV resolution it could look OK - anyone tried this?

JKT · Feb 11, 2006, 01:19 PM

On my PB I have used the S-video port to hook it up to a widescreen PAL TV. It isn't usable as a second monitor for text but is OK for e.g. palettes. What helped was to create my own custom profile for the TV where the contrast was bumped up and the colours were more saturated relative to the Mac screen (my TV tended to look washed out colour-wise too).

However, it is more than adequate for viewing DVDs etc.

harrisjamieh · Feb 11, 2006, 04:39 PM

Cool, cheers. Will C, I meant will I see an improvement using S-Video instead of composite. This may sound like a very dumb thing to say, but when I look at my TV screen really closely, you can see the individual pixels, and there appear to be way more than 756 x 576 (ish), so i'm a tad confused as to why TV screen quality is still so much worse than computer monitor quality

quiklee · Feb 11, 2006, 11:17 PM

My S-Video connector works perfectly with my Sony 51 inch Projection HDTV . . . . people never know the difference between Grey's Anatomy that's showing live vs. Grey's Anatomy I'm playing from my iMac! Good Luck with yours!

Will C · Feb 12, 2006, 09:06 AM

Originally Posted by harrisjamieh

Cool, cheers. Will C, I meant will I see an improvement using S-Video instead of composite. This may sound like a very dumb thing to say, but when I look at my TV screen really closely, you can see the individual pixels, and there appear to be way more than 756 x 576 (ish), so i'm a tad confused as to why TV screen quality is still so much worse than computer monitor quality

Yes, S-Video will look better than composite as it avoids cross colour (where B+W detail gets decoded as colour info) and can allow a higher bandwidth for the colour signals giving less blurred highly saturated colours.

The reason you might think there are more pixel on your TV is that on a colour CRT it uses quite a few of these dots for each pixel/line - typically 10-20 rather than the 3 (R+G+B) you might expect. It is a bit difficult to describe without a diagram why it is like this, but if you are interested have a search on Wikipedia for 'shadow mask' or 'aperture grille' - unless of course someone here can describe it succintly.

PM me if you want a flash animation of a shadow mask/aperture grill.

nJm · Feb 16, 2006, 07:42 AM

He did say he has a Sony *LCD* TV...

I take it the TV doesn't have a VGA or DVI input? Obviously that would be better than s-vido

harrisjamieh · Feb 16, 2006, 10:02 AM

Originally Posted by nJm

He did say he has a Sony *LCD* TV...

I take it the TV doesn't have a VGA or DVI input? Obviously that would be better than s-vido

Unfortunatly not, as its not HD (hence no DVI), and Sony didn't bother adding a VGA. Damn You Sony

Will C · Feb 16, 2006, 01:33 PM

Originally Posted by nJm

He did say he has a Sony *LCD* TV...

Oh yes, sorry must read more carefully.... <embarrassment>