Inspired by the DSLR pinhole movement, I decided to do something similar. In the end I came up with this simple-to-make macro lens, made from a single-use Fujifilm QuickSnap camera and a body cap for the DSLR.

Part list
- Donor camera
A fixed lens toy camera, like the single-use Fujifilm QuickSnap camera.

- Body cap for your DSLR
I have a Nikon DSLR and so I used a Nikon compatible body cap.

Tools needed
- Drill
For step 3

- Sand paper
For step 3

- Duck tape
For step 4

- Knife and screw drivers
For step 1

Example photos
http://www.flickr.com/photos/aweijnitz/sets/72157624408118962/

Step 1: Strip Lens From Donor Camera

Find a cheap camera with a fixed (non-zoom) lens. I used an old single-use QuickSnap camera from Fujifilm, but any similar lens should do. Take it apart and remove the lens.

Save the electronics for future projects. :-)

Step 2: Prepare the Lens for Mounting

Using the parts from the donor camera, make a flat surfaced lens "package" to be mounted on the base (later step). The cheap plastic lens in the single-use camera came off and in the end I had to glue it back and then file down the plastic parts to be flat. The duck tape is there to even out my bad filing...

The purpose of the flat bottom is to came up with a lens package that is easy to fit to the base with minimal light leakage from the sides. If it isn't flat, more light risk bleeding in from the sides.

Step 3: Prepare the Base

Drill a hole in the center of a body cap for your DSLR camera. The diameter is not important, just as long as it is not too big to be completely covered by the lens and big enough to not obscure the light coming in through the lens. The hole I drilled is 6.5mm in diameter.

Rinse the finished part carefully to get rid of dust and particles.

This is the base piece that will carry the lens and attach it to the body of the camera.

Step 4: Attach Lens to Mounting Base

Using tape or glue, attach the lens package from step 2 onto the base from step 3.

Align the center of the lens with the center of the hole. Make sure all sides are completely covered by the seal so that no light can bleed into the camera body form the sides. I used duck tape to secure the lens onto the body cap.

The lens is now ready for use.

Step 5: Mount Lens on Camera

Fit the finished lens to your camera and go out and take some pictures. You will have no focus nor f-stops, since it is a fixed-focus, fixed-aperture lens. Just lean into the the motive to focus, take a light reading and adjust the shutter speed to get a correct exposure.

Example photos
http://www.flickr.com/photos/aweijnitz/sets/72157624408118962/