How do I use the eydropper to select more than one sample point? I've tried holding down CTRL and it only lets me select one sample point.

Click and drag to make a selection area. Usually you'll find an area of your screen that represents the full range of color/luma that you want to key. You can stack multiple chromakey filters for clips that need it.

Vegas has all the basic tools for chromakeying, although you'll work hard to create spill supression, which is one step on many other keyers (you'd use the secondary color corrector for this).

Keith Kolbo wrote an advanced chromakey tutorial for VASST that covers chromablur:
http://www.sundancemediagroup.com/articles/chromablur_by_kolbo.htm

Some people like to start with a secondary color corrector to make the screen more uniformly green before cutting the key. I usually don't, except when shooting a head-to-toe.

Click and drag to make a selection area.

Unless you're using Pro 9 as Sony changed it back to point-and-click with this version :-(

Whoops, I confess - I've not upgraded to 9 (but probably will on the next PC I build).

Click and drag for Vegas versions thru 8Pro to create a selection area containing a range of the screen chroma/luma you want to key...

How can one do multiple selections in V9?

The Newblue plugin for 80 bucks works a lot better than that thing they install on vegas. Also includes a PIP plugin and some other stuff.

I second Brian's comments.

Although I am a big NewBlue fan (and yes, I am also a beta tester so I am thoroughly biased in their favour!) I have only just this week for the first time used the NewBlue chromakey filter from their Video Essentials 2 pack.

It is waaay better than the bundled Sony plugin. Still not as kickass as good old Ultra 2 (in the Serious Magic days, not since Adobe ditched it) but I got very usable results from 'not bad but not great' footage. The spill reduction feature works well and the ability to widen the chroma range is useful for uneven backgrounds.

I would love to see a feature whereby the key is automatically generated from a frame containing ONLY the green/blue background, before the talent steps into frame. Meanwhile, this is a very good and inexpensive alternative (plus there's a load of other good stuff in the pack, as Brian mentioned).

Rats! Why would Sony elminate Area Selection? That's just crazy - most green screens are not perfectly lighted.

Ironically, I bought the NewBlue Effects 2 package this morning. So far, the Chromakey functions seems to perform only as well as Vegas, but there are a lot of goodies there for $80.

Has anyone tried Newblue's chroma key along with Sony's Chroma blur? I haven't yet, but the Chroma Blur enhances the stock sony keyer so maybe it'll give Newblue's a boost.