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slyguy
11-24-2003, 10:46 AM
I am having trouble selecting just the key on a composite source without the preview following it. From what I have read, I should just be able to de select the lock key check box but that does not seem to be doing the trick. What I want to have is Camera1 as my key source (green screen) with the background generator on the program to replace the green and still have the preview open so I can go to a new source. HELP!

JonCrowe
11-24-2003, 03:55 PM
When keying remember the following:

The Main bus will be your background source.
The Key bus will be your matte source.
The Preview bus will be your fill source.

Example:
American Flag clip on main bus as background source.
Green Screen dog on key and preview bus.
If I enable the key with these steps I will see the dog keyed over the flag. Now if I unlock the key bus and move preview to a live camera, I will see the live camera in the shape of the dog keyed over the flag.

I hope this makes sense give it a try and let me know.

slyguy
11-24-2003, 10:05 PM
Yeah that makes sense but my problem seems to be when I want to use the key from a live camera. In you example, you used the dog on the green. In that case, the dog is an internal source in the computer. I can select the key channel from it and the preview of another source. However, if I select a camera on the key bus, the preview follows it regardless if I have key lock on or off. I hope this makes sense. Any ideas?

Gordon
11-25-2003, 04:07 PM
You've answered your own question. You can only separate the key and preview bus when the key source is internal. You can't have a separate key and preview when your key is live video.

This is a limitation of VT - there are only two live video sources in the hardware! Three live sources would mean redesigning the VT card hardware.

I too would like to see this in the next hardware along with a 64bit 66mhz bus support so the sources could all be HDTV! :D

I guess this should be sent to 'vidfeatures @ newtek.com'

slyguy
11-25-2003, 10:13 PM
Thanks Gordon. I was afriad of that but I just needed someone to tell me.

mrceolla
11-26-2003, 06:22 AM
Is that still true if you have the breakout box. I was told that allows the toaster card to decode an additional analog source simultaneously.

Gordon
11-26-2003, 07:33 AM
No the breakout box still only allows two real time analog streams to be send through the VT card into the VT software for processing.

I guess that you can have a live firewire camera as an additional live stream. However, there is latency with DV and mixing a DV camera source with analog video doesn't work too well it the subject of both cameras are the same. I haven't tried keying a DV source so don't know for sure that it works independant of the preview bus. (Due to the 5 to 1 compression of DV, you may not be happy with the DV key anyhow.)