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Peter pan
04-08-2006, 11:41 PM
We use powerpoint slides in our church services, coming in from a second computer via network cable. Our projector is connected to the second vga-ouptput. The quality of powerpoint slides (using iVGA as a swichter source) is good, but never quite reaches vga quality. if we instead use the "send to vga out" method the quality is perfect (but this way we cannot fade in the slides; only hard-cuts are possible and we of course cannot see the source in the preview monitor).

is that normal or does the grafic card matter? does vt scale down the iVGA source to video quality (pal 720x576) before re-scaling it up againg to the used vga resoluition (we use 1024x768)?

pascal

rbartlett
04-09-2006, 12:01 AM
Pascal, could you tell us about the network hookup? Ethernet speed, what joins the machines (repeater-hub, switched-hub, x-over-cable,...). Whether there is a decent amount of CPU/RAM on the powerpoint end? If there is a personal firewall examining every packet that passes (e.g. the one that turns on in XP SP2 that might need tuning/or-at-worst-disabling).

Something seems wrong with the pump or the plumbing. Your VT is probably OK, but the network hose on that might have similar considerations.

Tarheel Cougar
04-09-2006, 12:08 PM
does vt scale down the iVGA source to video quality (pal 720x576) before re-scaling it up againg to the used vga resoluition (we use 1024x768)?

pascal

Yes, at least the NTSC version does. This is normal and has nothing to do with the video card because Tricaster acts the same way. Normally, the VGA resolution is scaled down with all your other switcher inputs. But when you use Send to VGA out, the VGA signal bypases the switcher and is very clean, but you can't switch sources. Its a tradeoff. You can try going back and forth after a transition, but that's the only solution.

Peter pan
04-10-2006, 01:00 AM
thanx alot, makes sense!!!

billmi
04-10-2006, 05:28 AM
The solution is to luma key the iVGA in the send VGA out options. Have the powerpoint machine output a black screen when you want the video sources from the switcher main out to show through, and have Powerpoint transition in the slides you want to show when you want them - and they will be in full VGA mix.

As you've figured, if you feed the VGA signal into the switcher it's going to be scaled down to NTSC, since you're switching in NTSC.