We used a shoebox to create our pinhole camera and used one of the longer walls as the screen. We contemplated using the bottom of the shoebox as the screen but this resulted in too short a focal length to be able to focus the digital camera. The inside of the box is covered in black paper except for the screen side, for which we used printer paper. There are two side by side holes in the wall opposite the screen, one for the camera, and one for the cardstock with pinholes which can be overlayed on the hole. To cover up any cracks in the box, we sealed the top of the box and any edges with duct tape. We used scotch tape for the cardstock with pinholes so that it could be easily switched out. With our orientation, the focal length was about 23 cm. Using the equation 1.9 * sqrt(f * lambda), we calculated the ideal pinhole diameter to be about 0.6757 mm. We ended up using the sizes 0.5 mm, 3 mm, and 5 mm as our pinhole sizes. The reason we didn't go smaller is that it is physically difficult to create a 0.1 mm pinhole.
Pictures were taken with 30 second exposure. Thanks to Brian Laus for letting us borrow his camera!
0.5 mm
3 mm
5 mm
0.5 mm
3 mm
5 mm
0.5 mm
3 mm
5 mm
We found that with the smaller pinhole, the image was clearer but darker. This makes sense because there are fewer light rays intersecting past the screen, and there is less light being let in. As we increased the pinhole size, the image becomes brighter but more blurry as the light rays interfere with each other more.
Although the images were blurrier, we chose to take more pictures with the 5 mm pinhole because of the issue of brightness. When taking the pictures, it was sunny outside and therefore very difficult to see the details and appreciate the sharpness of the pictures taken with the smaller pinholes. Only when we uploaded the pictures could we see that the 3 mm and 0.5 mm pictures were significantly sharper. So we took pictures of other scenes with the 5 mm pinhole.
Light painting is a photography technique in which you use a small lightsource and move it while a photo is being taken with long exposure. The resulting image looks as if you the movements you made "painted" an image of the light in the air. See our take on light painting here!
