Green Screen Induction Part 2!

Our next green screen induction involved keying and masking in order to replace the background with another, more exciting one! In this session we learnt how to do this in After Effects, but in live action and bigger productions, there are individual programs that will cater to masking out areas in a frame more accurately and distinctly (and more expensive!). To begin with, we imported our image sequence into After Effects, and changed the frame rate to a more appropriate one! (12 or 24). From the 'special effects' tab, we chose the 'keylight' option and dragged that onto our image sequence so that we would be able to experiment with the settings. From this we used the colour picker tool and highlighted an area on the blue screen and changed our background to a bright vivid colour, I chose red, in order to see which area of the sequence we would be masking! As you can see in the above image, there is also some red on the object which is a really bad sign, I did end up masking this out, but this meant that there was some blue highlights on the object which is best to avoid in the future.

We then switched the view from 'Final Result' to 'Screen Matte'. This switched our images from colour, to black and white. The black symbolised the part of the image that we were masking out, and the white included the parts that would be left. I of course only wanted the object to be kept, however there is white surrounding the border of the sequence, so I would later have to clip this out. As you can also see there is still some black parts on the object which would mean that they would turn invisible once I added a background in, so to eliminate this I used the 'Clip black' and 'Clip White' tools, to make the contrast more visible and distinct, and essentially getting rid of those black dots.

I then clicked on my image and chose the pen tool to draw around my object. I didn't have to be so precise around the top because the blue screen had done a good job of allowing me to mask it out, however those surrounding edges that glowed white did not and therefore I had to be much more precise to get the perfect windmill that I wanted.

This is the first test we did with only a small image sequence to get us used to the tools and steps, which I thought was very useful! I enjoyed seeing the final result, and how simple it seemed therefore I went and tried again with a longer sequence:

This one looks more realistic and fluid. I really enjoyed these tutorials because they opened my eyes to a variety of other things you can do on After Effects. I used this program a lot last year and not much this year, but I am truly grateful for these inductions because I think at some point in the next two years I would really love to try it out again!