CS 194-26 Project 2: Max McArthur & Regina Ongowarsito

The Camera

We used a standard shoe box and lined the insides with both black cardstock and black duct tape. To implement an “interchangeable” pinholes system, we cut a hole on the side of the box and created our pinholes on smaller pieces of black cardstock, which is then held in place on the box using binder clips. We did a similar setup for the digital camera -- we created a general cutout for cameras in the box, and for each camera we used, we surrounded the lens with black cardstock that fits into the aforementioned cutout on the box, with a circle cut-out the exact size of the lens. This way, no light is leaked in through the hole made for the digital camera, and we’d be able to change lens or cameras if we wished.

Results

Our box was about 8 inches in depth (image distance). Using the given equation, 1.9 * sqrt(f * lambda) to derive optimal pinhole size yielded 1.89 mm, so we decided to use values on either side of this, settling with the recommended 1, 3 and 5 mm sizes.

Size	Lower Sproul (15 second exposure)	Upper Sproul (30 second exposure)
1 mm
3 mm
5 mm

We found that quality of final image depended heavily upon the amount of light present and being reflected onto the box itself; we can see this in the pictures above by comparing those of Lower Sproul (where we placed the camera in a more shaded region) and Upper Sproul (where we placed the camera in direct sunlight). Ultimately, the smaller the pinhole, the more focused but darker the images will be, while the larger the pinhole, the less focused but brighter the images will be. In our case, the images using both the 1 and 3 mm ended up being pretty clear images, while the images using 5 mm holes appeared bright and out of focus. Given this, for our additional pictures, we decided to shoot in brighter locations with the 1 mm pinhole in addition to increasing the shutter speed to 30 seconds to compensate for the lesser amount of light going in:

Looking across Upper Sproul towards Sather Gate.	Looking down Telegraph Ave.
The view from the rooftop of Eshleman Hall.	A view of Zellerbach Hall. Fun fact: The plaza was full of skateboarders, none of whom are visible in the final photo.