HD downconversion in Vegas for EX1
 

So some folks are reporting that they aren't happy with the quality of downconversion to SD with EX1 footage. Here's something you can try:

(Optional: Render out your HD master to a single file / new track. If rendering to new track, remember to check video output FX so they don't render twice.)
Nest your project into a new .veg

On the clip, add the gaussian blur and unsharp mask effects.

In the bottom left-hand corner, you should see little triangles. Click the one beside Gaussian blur to change the Pre/post toggle. What you want is blurring before downscaling, and sharpening afterwards.

For the FX, pick the "light blur" preset for the Gaussian blur and the "Light" preset for unsharp mask. You can play around with the sharpening.

In the render dialog, I'd suggest you pick "good" quality for rendering.

This should get rid of the aliasing that you might see on diagonal lines and wires and such.