Cardboard Camera

Inspired by a contest on the site Farktography I decided to build a camera after researching just what a 'pin hole' camera was. Basically a light tight container with a sheet of photographic film and a small hole as the lens. Unfortunately, I have no idea how to develop my own film or even access to a dark room.

I did have access to cardboard, tape and my own digital camera.

The best picture so far with the Cardboard Cam 2

Cardboard Cam 1

The first of the card board cameras was made by guess work. I made a light tight box about 12cm high using an old box. The hole in the centre is the lens and the larger square hole is for my cell phone's camera. Rather than taking photographic film and using that, I decided to use another camera to take a picture of the image appearing on the inside of back of the box.

This is the best picture from Cardboard Cam 1. It is actually a flourescent light, right above the table where I built CC1. It is rather blurry and dark. Two problems with CC1 were the lens being much too wide (roughly 4x the diameter that would have been optimal) and the 'film' the cell phone's exposure being much too fast.

After some research, I found the formula to calculate the size of the hole for the lens.

d=1.9√(fλ）

Got a bigger box and created Cardboard Cam 2.

The small hole in the centre is the lens just like the first camera. However, now it is about half a millimeter in diameter. The larger hole is for the lens of my DSLR camera. The other tabs of paper with holes are additional pinhole lens for the CC2.

A pinhole camera has an extremely small aperature, letting in very little light. Experimenting with the length of time resulted in this interesting series of pictures.
I have left the images unedited and uncropped here. The round, white areas sometimes on the corners are parts of the outside of the cardboard box.

8 second exposure.

4 seconds

2 seconds

1 second

0.5 seconds

1/10 second

By the last of the photos in this series everything is looking quite dark despite it
being about 2pm. I think with if I refined the lens a bit more and used even shorter exposure time with increased magnification it might be possible to see details such as sunspots on the sun.

1/15 second
It might be the corona of the sun or blurring caused by the edges of the hole being used for the lens.

Another interesting effect using a pinhole camera is to use two holes at the same time.

Same as above, just cropped for effect.

Same shot as the first in the post, here uncropped. The pinhole lens casts the image not just on the back of the box but on all of the inside surfaces where a straight line of light can pass through the lens and hit the inside of the box.