In the podcast Episode 9, I mentioned using motion tracking to fix a wayward lapel mic in a patron interview for the CabbageKey.com website promo video. (Coming soon…unless you’re reading this after the fact. In which case it may already be online.)
It’s always handier to get things perfect in the recording phase; but sometimes when you’re doing run ‘n gun shooting on location, it is what it is. It would have been slicker here to have the subject hide the lavaliere (lapel) mic under the near lapel (and then see if we could prevent the scraping noises often caused by skin or clothing—lavaliere mics are notorious for picking up contact noise). We also could have tried to supply the second patron a more neutral colored shirt.
But no sweat. We were likely to do some color correction anyway (regarding the pink shirt); and hey, the lapel mic gives me a chance to do a little tutorial on motion tracking!
I suspect we will expand these two topics into full tutorials later…but for now, here’s a quick summary of what we did, with examples from the actual workflow.
Below: The source footage. Among other things, the saturated pink shirt competes with the main subject.
Below: After color correction in Adobe SpeedGrade. The pink shirt was desaturated and darkened a bit, and the second patron’s face was lightened a tad. These tasks can also be performed within After Effects CS6 using the Color Finesse plugin under Effects > Synthetic Aperture.
Below: Motion tracking in Adobe After Effects. Basically, two points (the tip of the lapel mic and the mic clip at the edge of the lapel) are selected and the motion tracking feature in After Effects analyzes the movement of the selected points during the clip. Note that it’s good to select points that have high contrast from adjacent areas. For this purpose, the two points on the black lapel mic and clip provide good contrast with the tan lapel.
Below: I put what I estimated would be the most useful frame into Photoshop and cloned/painted/smudged/etc. the lapel mic out of the pic. Then I brought the healed image back into After Effects and made a mask to place just the necessary healed portion over the lapel (with a little feathering to finesse the transition). If you notice the little blue motion tracking dots on Macy’s shoulder. I actually had to add a Null layer, and set it as the parent of the healed patch layer. The motion tracking data was applied to this null layer. The position of the healed patch layer can then be set exactly, and it will follow the motion of the parent Null layer.
Below: The final result. Among other things, the pink shirt is tamed, and the lapel mic is gone. Even though Macy is moving slightly during the shot, the healed lapel (sans mic) moves along with the video shot.
Also, in our Follow Up Friday interview with Carnese Jackson, Carnese mentioned a link to more info on motion tracking in After Effects. Here it is!
https://www.video2brain.com/en/lessons/overview-of-warp-stabilizer-effect (Note that although the page mentions the Warp Stabilizer effect, there are also a number of links to Motion Tracking tutorials.)
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