Through the glass effect

By Matt
We got this idea from the Clavin Harris music video "Feel so Close". We shot this particular shot from a number of different angles. However half way through i thought of the idea that what if the camera was t appear to go through the glass window of the passenger side on the car. I didn't exactly know how it would work but decided to have a played around. 

If the window was removed in the actual footage it would allow us to have a steadi camera path and then i could then just add this back in post production. Therefore we rolled the window down and manually focussed in the final position. Then with my hands just guided the camera slowly and steadily through the window into the camera to bring Doms hand on the radio into focus. 

 









Once we had the original footage i then had the task of editing it. Unfortunately watching it back i realised that all through i was trying my hardest to keep it as steady as possible there was still a reasonable amount of camera shake. Therefore i imported the footage into after effects and brought up the tracking window (images above). 

I then selected one part of the frame that stays in the shot throughout the composition (gear stick) to track the movements over time. This shows me the direction of the footage movement and any severe shakes will show in the tracking movements as there wont be a straight line. I then restricted the movement of the footage to allow for a steady flow as if the camera was gliding through the window. This produced the video below, as you can see there is a massive difference between the two shots (below). 


Once we had the original footage i then had the task of editing it. Unfortunately watching it back i realised that all through i was trying my hardest to keep it as steady as possible there was still a reasonable amount of camera shake. Therefore i imported the footage into after effects and brought up the tracking window (images above).

I then selected one part of the frame that stays in the shot throughout the composition (gear stick) to track the movements over time. This shows me the direction of the footage movement and any severe shakes will show in the tracking movements as there wont be a straight line. I then restricted the movement of the footage to allow for a steady flow as if the camera was gliding through the window. This produced the video below, as you can see there is a massive difference between the two shots (below).

Once this i had been done i began the task of adding in the window which i knew would take me a while as i was trialling lots of different techniques to see which worked. The one finally found to work was using a pre composite made up of multiple layers on a mask.

Firstly i started out on the first frame where the window was "biggest" and the most of it could be seen. I then created a solid layer and used the pen tool to draw around where i would want the window to be in the shot.

I then masked out the rest of the shot so only the solid layer was visible in the shape of the window. I then precomposed this shot, which turns the shot into a folder in other words so i would have to deal with lots of layers on the original project file. 

The next thing i had to do then was actually texture the video. The first thing i added was a gradient or ramp in after effects. Looking at the small window next to it i could see that the overall tone of the windows was a pale blue and it was slightly darker at the bottom compared to the top. I then added this on a alpha matte paired to the solid layer (pen tooled window) so that gradient filled the solid layers spot. When the opacity was lowered it gave a very nice effect (seen to the below) however it was just not realistic enough.

So i thought what else would a window have, dirt? The most obvious thing that can make a massive difference is the texture to the window not just the shade and positioning. I then imported an image of a dirty texture i got off the image. I colour corrected using curves and the toner to have a more blue base so it would overlay easier. I then added it to the pre-composite and increased the contrast/exposure slightly to make it slightly more visible. I then added a mask to the top as there would usually be only dirt on the bottom side of the window from driving. Then feathered it out to make sure there was a gradual development of dirt and not a cut off line between clean and dirty making it appear more natural.

The image was getting better but there was still something missing to make it complete, a reflection. Windows reflect there background and it was essential to add one to finally finish off the texture of the window. I went on the internet and found a image of a field with trees and a nice sky. As the car windows are slightly pointed up wards i made sure it was essential for a lot of the sky to be able to be seen. I then played around with the curves again to increase the contrast but also decrease the overall tone of the image as reflections aren't known for being the brightest. Finally this created a realistic window i was very happy with.

Now i had my window i had to track it to the actual video. Unfortunately there was no way of me being able to track to whole clip and pin the solid matte to that spot and the most of the matte eventually goes out of the shot, which meant i was going to have to do it manually. I pressed the key frame button on the shape of vector, position and scale and then skipped a head and repositioned all the attributes to fit in the shot again. This took some time but it meant i could personally make sure all the frames were in shot and rightly framed.

However when it got to the point where all of the sides of the window were out of shot, it was hard to guess how much the window would increase and move to throughout the rest of the composition. Therefore i used this graph see the past rate of scale and position and then projected this path throughout the rest of the frames.

I was now into the final stages of the shot. At the end of the shot i know had to create the illusion that the camera was travelling through the glass. I travelled to that point i thought it would in relation to the surroundings of the shot and lowered the opacity using keyframes so it would gradually decrease. I then wanted to create a sort of ripple that would happen across the screen to reinforce the illusion that we were travelling through glass.

Therefore i created another pre-composite of a white strip which i feathered out and animated to move across the screen at the same point we "travel" through the glass. Then created an adjustment layer with a displacement map making sure only the horizontal displacement was applied and parented the source of the map to the animated rectangle. So when we pass through the window the displacement map bends the video across the screen quickly. Finally render is below which i am very happy with.