VSync problems! Help needed urgently.

mattrshaw · 11-11-2009, 11:29 AM

Hello. Thanks in advance for any help you can give, I'm quite desperate.

I've made a video of a waterfall for a restaurant that's being projected.
YouTube - Pushkar Final Gold2 YouTube
This is the video.

It's running on Quicktime on a shuttle PC, on the PC monitor it looks smooth but when it goes through extension cable, vga amplifier and 2 way splitter and then ends up going through VGA to projector there is awful 'tearing' or vsync as I believe it's called. I'm assuming its not the media as it looks great on monitor, its just when its output via VGA to projector. I realise there is a lot of vertical motion in the media which may not help but convinced its not the media. HELP!!!

Any idea why this is happeneing? I've asked client to check vsync settings on graphics card but still not getting anywhere.

Restraunt is opening tomorrow night so getting quite desperate! I can get more info on setup if required.
Any help would be greatly appreciated as I'm in a real panic now.

Thanks,
Matt

choddo2006 · 11-11-2009, 12:31 PM

Which projector is it?

What exactly is happening that you're calling tearing?

Is the PC set to 60Hz output?

By the way, I can see tearing in that youtube vid on my laptop screen

mattrshaw · 11-11-2009, 1:54 PM

Thanks for the reply.

Don't worry about projector type, the fact that you see the page tearing on your laptop screen on youtube suggests the media is more to blame then I suspected. I've rendering out a new version at the sixth of the original speed and I'm seriously hoping that'll solve the vsync errors once for all!

I'd prefer to tweak the hardware to display to media correctly but given the looming deadline I'm thinking it'd be more sensible to tweak the media towards the hardware!

jgrg · 11-11-2009, 3:53 PM

I think you just need to make sure that the frame rate of the video matches the frame rate of the projector, or is a divisor of the projector frame rate (ie: 30 fps video displayed on 60 fps projector, or 25 fps video on 50 fps projector).

Barcoing Mad · 11-11-2009, 4:37 PM

When I get home I'll try this on my machine with ReClock. Should give the refresh rates etc.

mattrshaw · 11-11-2009, 5:12 PM

THank you very much for your help everyone.
I think it's as simple as that frame rate issue. Will try again at 30fps and 25fps and see if that solves it!

The lesson learnt here I think is that if the client specifies 24 fps without having a clue what the projector will be used, I should question it!!!!

choddo2006 · 12-11-2009, 12:39 AM

Quote:

Originally Posted by mattrshaw

THank you very much for your help everyone.
I think it's as simple as that frame rate issue. Will try again at 30fps and 25fps and see if that solves it!

The lesson learnt here I think is that if the client specifies 24 fps without having a clue what the projector will be used, I should question it!!!!

Ha, yes. If you're not sending 1080p/24 to a projector that supports it then there's no way you should encode at that rate.

jgrg · 12-11-2009, 11:34 AM

Quote:

Originally Posted by choddo2006

Ha, yes. If you're not sending 1080p/24 to a projector that supports it then there's no way you should encode at that rate.

If he is lucky the projector might work at 72Hz at lower resolutions.