Re: How to apply an effect in the only one segment of a footage ?

It doesn't sound like you did anything wrong and if it looks the way you want in the Vegas preview but not in the render it is more than likely a bug rather than anything you did wrong. What I would do is isolate the event you want to use Neat Video on and render that out separate. Then use the cleaned video in your project by adding it back to the event as a take. Then render the whole thing.

~jr

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