A camera obscura is the predecessor of modern day cameras. It works by letting light in through a small pinhole and projects it onto a surface (e.g. a wall).

To build a room obscura we need to choose a room which gets plenty of sunlight. I chose my bedroom for this.

Next we need to identify all the sources of light and completely seal them. In my case I used garbage bags to cover my two windows.

I used packing tape instead of duct tape as it can tear off paint from the wood. However, this led to some light bleeding in from the edges. I fixed this using aluminum foil.

I experimented with three pinholes of various sizes.

After trapping out all the light I mounted my camera next to my pinhole and captured the image.

This was the best result I could get using a pinhole of 0.4 inches.

Lessons learned

It is extremely important to perform this experiment on a sunny day, otherwise you will not get a clear image.

You should also experiment with different focal lengths, i.e. adjust the distance between your pinhole and the screen. This can produce a sharper image.