Wetpixel

Flash Removal Using a Virtual Clip

We've all suffered the indignity of having a thoughtless still photographer ruin our perfect shot by firing off their strobes. This somewhat complicated tutorial shows how I remove an unwanted strobe firing from a clip I otherwise want to use. See the final result in Quicktime or RealVideo here. See the original source in Quicktime or RealVideo here. For whatever reason, my Quicktime encoder insists on ruining these files, so please use the RealVideo files if you can. If you just view the Quicktime files you may think I'm crazy.

In the first picture I have the clip loaded on video track 1 and have marked the location of the strobe fire on the timeline. Not only can you see the strobe illumination, but the photographer couldn't stay out of my way, either. We'll fix both and the technique will make it easy.

 

 

The first thing I do is move the clip off the end of my editing timeline. In this case I put it at the 12 second mark but normally it would go after the music I've selected. I then select the bad frame using the marker, zoom in to "1 Frame", then back up exactly one frame as shown in the second picture.

 

 

Then I export a single frame (File->Export->Frame) of video saving it in the project directory where I store my clips. I import this frame into the project, set its duration to 1 frame, then drop into onto the Video 2 track directly aligned with the strobe frame. What this does is replace the offending frame with the one before it. During day dives, only one frame is generally effected. If more than one frame is effected, you can replace more frames but you must be careful to avoid the appearance of a stutter. Sometimes, minor strobe effects can be removed with keyframed color correction, but I am not covering that here.

 

 

Now we have our strobe removed and want to put it on our actual timeline. We select the virtual clip tool as shown in the next picture, lasso the clip including the still overlay, then drag it onto the location we want.

 

 

Now we have a virtual clip that is just like the original except that the strobe frame has been replaced. You may wonder why the extra step of the virtual clip is of value (and I'll tell you). All subsequent filtering, effects and transitions you may want to do now will apply to the corrected clip. Without this step, the correction frame will always be in your way.

 

 

The next step is to zoom in on the subject to remove the thoughtless photographer. We do this by enabling motion, centering the beginning and end of the clip, and entering a suitable zoom value for both endpoints.

 

 

The final picture shows that I have added some of my favorite color correction. The purpose of this is to show that I can fix the strobe problem, then treat the fixed clip just like any other footage. Since color correction is something you usually want to do here, using a virtual clip is the right thing to do.

 

 

This particular clip has some flash overhang into the second video frame as they frequently do. I left this in to see if anyone would see it. Often times you don't need to get something like this perfect. Once below a threshold no one will notice it.

Enjoy!