Saturday, November 5, 2011

How to make a pinhole camera

Over a month ago, I had made my first random object pinhole camera.  I made it from a thrifted teapot and shared those images here from this past post.  The camera and images were such a success and each image unique.  I love the idea of taking everyday objects and incorporating them into a photographic way.  So now I'd like to pass the knowledge around and give my own tutorial on how to make one!

To begin with, you need to find a light tight container to create your pinhole camera from.  The easiest and most convenient are old metal tins.  Beware of paper/cardboard containers!  Though they may seem sturdy and light tight, unfortunately they are not thick enough to withstand strong sunlight.  Even if you cannot find an old metal tin, many objects can be made to be light tight.  (Like my teapot!)  You just need to be creative and think of ways to block out the light.

Here above is my example tin that I will be showing how to make a pinhole camera from.  As you see the tin has a shiny golden inner surface.  Unfortunately that will not work for the success of the pinhole camera.  Believe it or not, but light can bounce!  And when light enters your pinhole, it will indeed bounce around, causing it to refract around, creating an obscured and less successful negative.

To solve this problem, you will need to coat the inside of the tin with a matte black paint.  Matte as opposed to glossy black is important because it is the only black that will not allow light to bounce around inside the tin.  I used Rust-Oleum Flat Protective Enamel in matte black.

Spray the entire inside of the tin.  Let it dry overnight.  Don't forget the lid too!

Here you can see my post-spray painting hand.  Good tip on removing spray paint: nail polish remover

Next you will need to create your lens or "pinhole plate".  You will need an empty soda can and a pair of scissors.  Cut a small square piece from the can.  Be careful of the sharp edges!

Go back outside and spray paint this small piece of metal, both front and back.  Allow to dry.

While the small piece is drying, prepare the tin for the pinhole plate.  I used a 1/2" drill bit, (meant for wood, just a good on old tins) to create the hole.

Next you will need the dried piece of metal from the soda can, a sewing machine needle and some basic math.  I used size 14 needles.  That hole diameter comes to 0.014mm.  This number will help you determine the f-stop of the camera.

In order to calculate the f-stop you need to divide the distance from the pinhole to the imaging plane by the focal length. 

This means: 
Find the distance from the front of the tin to the back of the tin. 
Answer:  4.25" 

Divide that number by 0.014 mm
Answer:  Roughly 304 

My f-stop is then f/304

This number is important because it helps you calculate your exposure time when "shooting".  It is the difference between sunny days (4 min exposure) to cloudy days (15 min exposure)  You can find a lot of information on the internet to better calculate a closer exposure time from various time exposure charts.  Here is one I found quickly as a reference guide.

Anyway, back to the rest of the tutorial.  Pierce the thin metal with the sewing needle just enough to cleanly come through the metal.  Do not over emphasize piercing the hole because you will undoubtedly create a larger diameter.

Next you will need to gather together a pair of scissors, black electrical tape, your tin, and the prepared pinhole plate.  Place the black tape on all four edges of the pinhole plate.  Use your scissors to cut the specific sized pieces of tape.

Carefully place the pinhole plate into the camera, centering the actual pinhole with the drilled hole of the tin.

And you're done!  Make sure to place one more piece of tape back over the outside of the pinhole!  This is your "shutter" of the camera. 

You'll need to load the camera with light sensitive paper in a darkened room or through a photographer's changing bag.  Then go outside, find a safe spot to set your camera down on, remove your "shutter" tape and start exposing!

Here I took a photo of what my pinhole camera was taking a photo of!  Not a very exciting image I must say but quirky and fun enough to not matter.  :) 

Afterward, develop your light sensitive paper through typical development processes and you'll create a paper negative that you can reprint over and over again.

Good luck in making your own pinhole camera and feel free to email me with any questions!

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