My HTPC, when connected to the HDTV, it is connected through HDMI. So naturally the image quality is fantastic. On my old CRT TV, I have the VGA port outputting to a converter box http://www.amazon.com/Lenkeng-104724-Monoprice-VGA-RCA/dp/B001CJOLBW/ref=sr_1_1?s=elec...ice+VGA+to+RCA. Then S-video from the converter box running to the CRT TV. While the quality is all I could hope for, on fast moving scenes, or scenes with flashes of lightning, the image has a "rolling shutter" effect (this effect also exists after some amount of time, even without fast-moving scenes or great changes in the lighting of the scene), such that there is a horizontal disconnect where the previous frame is on the bottom and the new frame is on the top. However, it is an incredibly slow correction, it takes about 8-12 frames for the "rolling shutter" to finish "rolling". Any ideas on how to avoid this besides buying another HDTV?
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Thread: HTPC Image Quality Problems
It probably looses sync and that causes the rolling. You might be able to change your VGA card settings and get some improvement, but that would affect any PC VGA monitor connected to the card.
Graphics cards can usually only vsync one output. The second (third, etc.) will suffer from tearing -- what you are seeing. The only way you can avoid this is to use only the HDMI output of the graphics card, then an HDMI splitter to an HDMI-to-composite/s-video converter (the other HDMI output of the splitter goes to the HDTV).
Maybe I'm not being entirely clear. The HTPC is never connected to both the CRT TV (though VGA) and HDTV (through HDMI) simultaneously.
Does the tear continuously roll or does it only happen once? In any case, try different VGA resolutions and frame rates. Especially very old standards like 1024x768 at 60 Hz. Or 800x600 at 60 Hz.
It happens continuously, as in there will be one tear every two minutes (roughly), or when there is a huge difference in information between frames. It is currently running at 1024x768@60hz, seems to happen with 800x600 as well.
Do you have any VGA monitors or TVs? Try plugging the computer into that via VGA. See if it's the graphics card's fault or the converter's.
I have an identical looking converter. I used to use it with a laptop. I don't recall it having problems with tearing.
Do you have the little toggle switches set correctly?
Last edited by jagabo; 7th Jan 2014 at 18:16.
Brilliant idea, I'll try it with my VGA monitor.
The toggle switches are in the correct position but due to a manufacturing defect one of the switches cannot go completely into the up position, there is some plastic in the way. I doubt that's the cause, but maybe I'll take it apart and cut off some plastic so the switch can be seated in the up position.
Well, you got my curiosity going. I broke out an old laptop with VGA output and the VGA/composite adapter. The fault is in the adapter. I used a test video with vertical lines scrolling horizontally. A perfect tearing test. There was no tearing on the laptop screen. Running VGA directly to a TV showed no tearing (clone mode). But running VGA to the converter then composite to the TV showed tearing. About once every 20 seconds a tear would move quickly down the screen, over about a quarter second. I guess that's why it sells for $15.
I tried 640x480, 800x600, and 1024x768, all at 60 Hz. I suspect you might be able to alleviate the problem if you can set your graphics card to 59.94 Hz. I also tried all four switch positions. One switch didn't seem to make any difference. The other was obviously a PAL/NTSC switch.
Wow that was very nice of you! Thank you very much, its nice to know where the problem lies, although I probably won't replace the adapter since I'll likely be replacing that CRT TV with an HDTV or projector soon.