Replacing lens reflections in sunglasses during post-production is the easiest and most efficient way to get the reflection you want. Here’s how to do it.
Top image via The Matrix.
In The Matrix, Morpheus offers Neo two choices: take the blue pill, the conversation ends, and Neo will wake up thinking everything was a dream. Alternatively, he can take the red pill and see “how deep the rabbit hole goes.”
It’s a fantastic scene, and one of the most memorable elements is the framing of the shot when Morpheus offers both pills, which we see reflected in his sunglasses. There are a few ways of setting up your shot to capture a reflection like this, but let’s have a look at the easiest and most efficient method: doing it in post.
Note: this technique is for stationary shots with the subjects in a medium to close-up framing. Anything more elaborate, and you might need a different approach. It is also important to capture the reverse shot with a wide-angle lens — the wider, the better. Since lenses are convex, we must slightly skew the reflection. The wider the image we have, the more realistic the reflection will look.
Ideally, you will use empty frames, so you can build the reflective surface from scratch, which is much easier. However, if you already have a reflection in place, you can use this to your advantage with blend modes.
Step 1: New Composition
In Adobe After Effects, create a new composition and bring your sunglasses footage into the timeline.
Step 2: Placement
Then bring your reflection footage into the composition and scale it down over one of the eyes until you are happy with the size in proportion to the lens. Duplicate the reflection layer, but hide the copy for the time being.
Lower the opacity of reflection layer 1 to 1-10%, and with the pen tool, draw around the inside of the sunglasses frame (make sure you are still working with the reflection layer).
Now activate reflection layer 2, and again place this over the second frame. Unlike the scene in The Matrix, we don’t want our reflections to be so identical, as it’s not that realistic. Naturally, there will be a slight offset between both lenses. Therefore, slightly move the reflecting layer over a bit. I find that it looks most realistic when the furthest object of the first layer, is just slightly out of frame in the second layer. Hit F to bring up the feather on the mask, and set it to 2-3.
Step 3: Turn Reflective Layer Into A Lens
If we return the opacity back to 100%, you can see it doesn’t look that great just yet. It might be somewhat passable for a still picture, but not for motion. Let’s make the reflection look more realistic. First, add a bulge effect, and increase the horizontal and vertical radius to fill the entire frame of the sunglasses. You only need to increase the bulge height ever so slightly. 0.5 should be okay.
Because of the convex shape of the lens and the frame itself, the outer area of the lens will be slightly darker than the middle. To create this effect, add a CC Vignette. As the size of the affected area is relatively small, you can increase this quite a lot without the effect becoming detrimental. I’ve increased the vignette amount to 500.
At the moment, the exposure of the image is too high, so we’re going to add an exposure effect to the picture and lower it. Again, you only need to lower this a little. The frame is starting to look more realistic, but we’re not there yet. Since we are focused on the subject, realistically, the image in the reflection would not be as crisp, so we need to soften it. We can do this by adding a gaussian blur at anywhere from 5-7.
Now, this is starting to look a lot more realistic; however, because we are building upon a reflection within already established sunglasses, we can take it one step further and blend them both together. By doing this, we also receive image data from underneath the sunglasses. In this example, we can very slightly see the woman’s eye. However, we are also getting some of the image from the original reflection. Don’t worry, at this scale and with the new, more prominent reflection, it’s not going to be that noticeable. Set your blend mode to screen, and lower the opacity to 60%-70%.
Step 4: Track Movement
The reflection now looks very realistic, almost as if it were part of the scene to begin with. However, we have to implement tracking.
Double-click your footage and open the tracker window. You need to select track motion and create a tracking point for the position and the scale and place them at either side of the frame.
Next, create a null layer, edit the target to the null, and select apply. Finally, parent the reflection layer to the null object.
You should now have a well-tracked reflection. However, if at any point your actor turns and obscures the sunglasses, you will have to keyframe the mask into the correct position. This, unfortunately, is a painstaking process that you cannot skip.
The Result
There are many different blend modes you can play around with until you find the one that works best in your shot. Since the first reflection wasn’t that prominent, I’ve been able to use it to my advantage. However, if the reflection in your shot is quite apparent, follow the steps above but create a black solid underneath your reflection footage (with the same mask and tracking) .