CS 194-26 Image Manipulation and Computational Photography

Project 2: Camera Obscura

Mher Mnatsakanyan (cs194-26-aac)


The goal of this assignment is to build a pinhole camera, which is also known as a camera obscura. The Camera Obscura is basically a box that has a pinhole in one side and a screen on the opposite side. The light reflected from the object goes through the pinhole and hits the screen. However, it is hard to see the object on the screen with the naked eye, but it is possible to see using a digital camera with a long exposure time.


I picked a medium size Amazon delivery box (70 cm x 15 cm x 30 cm) when building the pinhole camera. On one side of the camera, I made two square holes, one for the light, the other one for the camera. In order to be able to change the size of the pinhole easily, I made 3 cards with 1, 3, and 5 mm holes and covered the original square hole with those cards. The second hole is for the camera. For the purposes of this experiment, I used Google OnePlus 6 phone camera, which has a pro mode and is able to take long exposure images. Here is a picture of me taking an image with my pinhole camera, both holding the phone and the card on top of the square hole.

My pinhole camera

All the inner walls of the camera are covered by black paper, except the screen, which is covered by white papers. I also duct taped the edges of the box from outside to avoid light exposure.


During the experiments, the exposure time of the camera was 30 seconds and the ISO was put on 1000. I tried different settings but those were the ones that worked the best. Here are some of the results:

The real photo, 1mm, 3mm, 5mm in order

Here is another one:

The real photo, 1mm, 3mm, 5mm in order

As you can see, the results for 5mm are the best ones, even though there is a significant amount of blurriness in the images. Since my phone camera had limitations when it came to the exposure time, 1mm and 3mm were not as good as I expected. The reason is the amount of light on the screen because the small pinhole size would be more precise but would take a longer time to take a picture. After doing those experiments, I just took the rest of the images with 5mm hole. Here are some pictures.

Additional Pictures:

The following images are taking with 30 secs exposure time and with 5mm hole size.

California Hall

Doe Library

Evans Hall

East Asian Library