With the release of recent montages and trailers, the need for this sticky has become greatly apparent.
Interpreting your frames correctly is key to making a video look professional. What do I mean? Well for example, when you see someone slow down their footage, and it gets all glitchy and shaky...it's because they're not interpreting their frames correctly.
The default mode for Vegas 6.0 is Lower Field First, however...some capture cards, notably the Dazzle 90 capture in Upper Field First.
To solve this problem is usually simple, when you start a project if you know your card captures in Upper Field First simply go to File then Properties in Vegas and go to the Video tab. Change the Field Order from "Lower Field First" to "Upper Field First", and you're set.
Now, what if you're putting clips together from different capture cards that don't have the same order? Don't worry it's a little painstaking but not too hard. For each clip that isn't interpreted correctly, or from the cap card that doesn't follow your general settings in Vegas...simply right click on each clip and change the field order appropriately. This can be done by right clicking on the clip in the timeline and clicking properties. Then hit the Media tab and change the field order like this:
There you go, no more glitchy slow mo.