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Hack 14. Build Your Own Blue Screen
You can build a large—in this case, 24' x 8'—removable, disposable blue screen for under $30 .
As a child in the late 70s, I was first introduced to the concept of using a
in film and video while watching
The Making of Star Wars .
The compositing technique of
1.15.1. Understanding Your Needs
Professional-grade compositing material can be costly, but almost any solid
Building your own blue screen is actually easy, and the whole project can be completed within a couple hours. The finished screen
The materials are lightweight, making it possible to build a portable version if needed. In fact, I produced a martial arts instructional DVD that actually employed a portable, green screen version of this setup.
I strongly recommend attempting to shoot a few shots against a small piece of material and testing how well you can composite with it using your lights [Hack #22] , camera, and software [Hack #70] before spending the time and energy to build a large screen. Once you're confident that it will work, go ask your parent or spouse for permission to cover one or two walls with the stuff. Most of all, have fun!
1.15.2. Gathering the Materials
In order to construct your blue screen, you'll obviously need a set of materials. This will require a run to your local strip mall to pick up the following
You should make sure you get a parent or spouse-approved room for the project. My spouse-approved room was an unused storage room in the basement. This was good for me, because it also happens to be the largest room in the house! Figure 1-21 shows me assessing the concrete wall.
The strips used to mount the blue screen are removable, but the Liquid-Nails will leave a mark on (or strip the surface of) concrete. If you screw the strips into drywall, the
1.15.3. Mounting the Pine Strips
The blue plastic is thin enough to see through if it lies against the wall, so you might want to use the strips even if you're mounting on plain drywall. I couldn't really mount the plastic against the brick wall; plus, the wall would show through. The strips leave a gap between the plastic and the wall, and they make it easy to mount the plastic by just using staples.
Figure 1-21. Assessing the concrete wall
Before mounting the strips to the wall (as shown in Figure 1-22), make sure you measure for fit and cut the strips to
Figure 1-22. Carefully mounting the pine strips
Finally, mount the strips along your
I was mounting to cinder blocks, so I used a can of Liquid-Nails. Liquid-Nails is like caulk, but it becomes much harder and stronger. It
1.15.4. Adding the Blue Screen
Now, we can finally mount the blue screen itself, as shown in Figure 1-23. Roll out the length of material needed and start stapling! Work across from one side to the other. Use three or four staples per
Figure 1-23. Mounting the blue screen
Make sure you pull the material as tight as possible without tearing for each staple to keep the finished screen flat. I goofed when placing the pine strips, and they were too far apart to completely overlap the two pieces. To fill the gap, I just used some blue, painter's masking tape. Figure 1-24 shows the completed blue screen, along with the painter's tape to cover the goof.
Hopefully, you will learn from my mistake and measure it properly from the start.
Figure 1-24. The final blue screen
1.15.5. Adding the Finishing Touches
To finish, I added some excess material to the top and bottom as well as to the adjacent wall. I did cover over the basement door, but the strips are screwed into the door frame rather than glued to the wall.
But does it work? Sure it does! Figures 1-25 and 1-26 show two examples of composites done using this blue screen room.
Figure 1-25. Shot on the home-built blue screen
If you would like to see some of the video created using this blue screen, you can check out the movie at the following URLs:
You just have to love digital video technology!
Figure 1-26. A successfully composited image
— Nick Jushchyshyn
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