I covered this in episode 44 of Learn Lightroom 5 and in Episode 19 of Photoshop For Photographers. In this episode of Learn Lightroom 6/CC, I demonstrate a different way to convert and process your scanned negative in Lightroom.
At the end of the video I mentioned that I'd like you to become my Patreon. Your kind support is greatly appreciated! You can check it out here:
http://www.Patreon.com/AnthonyMorganti