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tvwonder
11-17-2004, 11:34 AM
Hello,
We have just purchased VT4, PCI cards, and we already own the SX-8 BOB. The main reason why we made the switch to VT4 is because we are wanting to use Toaster as a source for a Grass Valley switcher as well as using Toaster as a DSK. We have Genlocked all of our sources including Toaster. Our problem is that when we switch to Toaster from the grass valley are colors look great, but as soon as we use the DSK from the grass valley are colors are all off.

PIZAZZ
11-17-2004, 11:41 AM
Hello,
We have just purchased VT4, PCI cards, and we already own the SX-8 BOB. The main reason why we made the switch to VT4 is because we are wanting to use Toaster as a source for a Grass Valley switcher as well as using Toaster as a DSK. We have Genlocked all of our sources including Toaster. Our problem is that when we switch to Toaster from the grass valley are colors look great, but as soon as we use the DSK from the grass valley are colors are all off.


Sounds like a timing issue between the GV and the VT.

Time for the trusty external Waveform/Vectorscope and a Calibar.

Jim Capillo
11-17-2004, 01:02 PM
Hello,
We have just purchased VT4, PCI cards, and we already own the SX-8 BOB. The main reason why we made the switch to VT4 is because we are wanting to use Toaster as a source for a Grass Valley switcher as well as using Toaster as a DSK. We have Genlocked all of our sources including Toaster. Our problem is that when we switch to Toaster from the grass valley are colors look great, but as soon as we use the DSK from the grass valley are colors are all off.

GV's are known for touchy and precise adjustments. A quick solution is to install a delay box between the feed to the GV from the VT - it has a combination of switches that change the phase timing without looping huge amounts of coax on the floor.

But ultimately, the timing adjustment on the GV is the way to go. Get the book out..... :eek: :D

kltv
11-17-2004, 11:58 PM
You might look at a sub-carrier adjustment. If there is no horizontal shift then you shouldn't have to worry about that. A color shift could be fixed by making sure the sub-carrier is setup properly. I think the toaster has that in the preferences section under Genlock or timing.

Kris

JReble
11-18-2004, 08:24 AM
I'd echo all of the above. The GV switchers are insanely sensitive to phase delay where many other equivalant components adjust to it just fine. At times with some components, the subcarrier adjustment wasn't enough to get it in phase. The GV would see some signals close to 180 degrees out and you couldn't compensate for that in some cases. The delay box was usually my preferred method, but sometimes (depending on your setup) you can simply make your video cables the correct length to compensate for the problem enough where your subcarrier adjustment can bring it fully into phase. I found a phase adjustment of approximately 1 degree for every four inches or so of cable. Often times all it takes is making your cable from one syncronous source exactly the same length as the other(s) then they can all be very close to in phase with each other. Sometimes depends on the equipment however, and whether or not the equipment itself in creating any phase alteration internally.

Jim_C
11-18-2004, 08:27 AM
Man, thats 4 replies full O' Info right there!!

Jim Capillo
11-18-2004, 08:31 AM
Sometimes depends on the equipment however, and whether or not the equipment itself in creating any phase alteration internally.

Ain't that the truth !

I can remember years back where we had an Amiga computer with Broadcast Titler going into a JVC switcher. The JVC had no provision for compensating for the phase differential (strangely enough, you could change the H-phase) and we ended up with about 120 feet of cable coiled behind the console to get it in phase. We were able to eliminate that when we got next year's budget and purchased the delay box.

The things you learn in cable TV....... :p :D

tvwonder
11-18-2004, 09:01 AM
Thanks for all the info. This will help us so much!!!