you can do 3d track motion to it too.

In some applications, this is called a "cast shadow". You might be able to maniplulate on second duplicate track using 3D and blur.

Dave T2

There are 3rd party plugins for After Effects that make this pretty simple. However if you don't have AE the tutorials on how to use them are still worth watching to see how it's done and then you can almost certainly achieve the same outcome just using Vegas and more manual work.

As other have suggested using 3D track motion will allow you to move and skew your shadow to make it longer. Then you need a blur that simulates distance, the further away the shadow the blurier it gets. You can use gen media to create a gradient to control the blur.
Then you need to blend the furthest away part of the shadow into the background colour. Again a grad mask will let you control opacity to achieve that or you can use a color grad and blend that into the shadow.
If the background is not smooth you'd also want to consider a height map so the shadow follows the contour of the background.

All this is doable with Vegas if your light source is static. If not then you're in for a huge amount of work using Vegas and then I'd really start thinking about using AE which gives you lighting control and you can make the shadow track the moving light source (say the sun).


Bob.

depending on the amount of detail, this could even be done really simple in a 3D app (blender) by making a graphic if your text & using shadows on the non-alpha parts:
http://img174.imageshack.us/my.php?image=alphashadowsri9.jpg[/link]

Bluff Titler can do this pretty easily

Thanks for giving me some ideas. The shadow look that is needed is for a subject shot on greenscreen. I may have to go to a friend who has AE to do it. Bob, do you know what 3rd party plugin will do that in AE?

Paul

"The shadow look that is needed is for a subject shot on greenscreen"

http://library.creativecow.net/articles/onneweer_barend/keylight.php

http://library.creativecow.net/articles/stern_eran/02_RG_Shadow.php

They're the first ones a quick Google found for me. No doubt there's many, many more tutorials and clues around.
There is a good forum on COW for After Affects, probably better off asking over there if you or your friend gets lost.

Bob.

> The shadow look that is needed is for a subject shot on greenscreen. I may have to go to a friend who has AE to do it

I've followed several AE tutorials on adding shadows and there wasn't anything in there that couldn't be accomplished in Vegas with 3D Track Motion. You may be able to do this in Vegas alone. Whenever they use a comp in AE think Nested Project in Vegas. You'll be amazed at what Vegas can do.

~jr