Introduction: WTf-stop: Digital Pinhole Experiments
This instructable documents a class I taught on digital pinhole photography for the Maker Lab at the Harold Washington Chicago Public Library. Pinhole photography is not relegated to film only as you will see and the benefits of experimenting with it are many but include
- relative infinite depth of field ( the range of what is in focus in a photograph )
- great forced perspective photography as you can see in intro photos (because of the great depth of field)
- natural vignetting
- natural light bleeds
- photography without a lens!
- an element of uncertainty that will even fool your DSLR light sensor!
- a way to understand how your eyes perceive images and focus ( by the way your eyes f-stop = f/3.2 )
The pinhole technique illustrates the principles of photography dating back to the camera obscura (dark chamber in latin ), which has been understood since around 400BC in China, utilized much later by artists such as Caravaggio and now by many contemporary artists and engineers in extraordinary ways.
METABOLIC STUDIO- Optics division (L.A. based with national satellite projects)
... I will have an update soon with a tent camera obscura I made at the Ox-bow School of Arts in Michigan soon.
Step 1: Gather the Materials for Your Pinhole
Making a digital pinhole is similar to making a film pinhole - the difference in essence is only how you capture the light - instead of using film emulsion we will be using our DSLR's (Digital Single Lens Reflex) digital sensor.
* Here is one of many great instructables on how to make an analog pinhole camera*
* There are also some great instructables on turning your phone into a pinhole, which we did at the Maker Lab as well*
Materials you will need:
1) A DSLR camera i.e. rebel, nikon etc. ( a remote or timed release shutter if possible)
2) Tripod ( this is very useful for most photo sessions and will allow you to take pictures even in very low light settings, which the inside of your pinhole camera constitutes)
3) One of the following with preference in this order gaffers Tape (any color), duct tape, scotch tape
4) Scissors and or a utility blade
5) Sewing pins ( preferably those used for hemming with round plastic on the end-otherwise get a thimble)
6) Pen or pencil
7) Super glue
8) Cardboard - preferably a sturdy thin piece (cereal boxes and other food packaging are a great resource)
9) Aluminum ( not aluminum foil- you will need a thicker material ) - I recycled votive candles and cut them up to find mine) you could also use metal bottle tops.
10) Objects to photograph big and small ( the advantage of pinhole cameras are their depth of field, which allow you to crate forced perspective i.e. the illusion objects are the same size or are closer together than they are in reality because of they image composition and focus - see intro images for an example)
11) LIGHT - you either need to work outside in strong daylight or have a strong lamp that you can use as the f/stop of a pinhole camera is f/330 ( that's insane! ) , which means there will be very little light that is able to make it into the camera, therefor bright light and long exposure times ( must have a tripod, and a means of remote or timed shutter release) are going to be our friends.
Step 2: Prepare Your DSLR to Become a Pinhole Camera
1) Cut a roughly 2in x 2in cardboard square out with either a utility blade or scissors, this dos not have to be perfect but needs to be large enough to completely cover the lens ( you can check the size by placing the square over your capped lens to see )
2) Draw a circle or square slightly larger than the size of a pencil erasure as a guideline.
3) Carefully cut out the square around the circle making sure not to slice beyond the guideline edge if possible.
4) Turn over the cardboard and cut out the same shape if necessary.
5) Apply dots of super glue on the perimeter of the cutout shape.
6) Carefully place your small piece of aluminum over the cutout and press down with your fingers. ( the aluminum needs to be thicker than foil - you can use either a bottle cap or the shell of a votive candle as I did for this pinhole )
7) Flip you cardboard with the adhered aluminum over so that the aluminum is making direct contact with your cutting surface as this will provide a more flush surface to puncture ( slide another piece of cardboard under the foil if need be to protect your working surface from puncture holes )
8) Carefully take your pin with a thimble if needed and lightly press on the aluminum rotating the pin between your thumb and pointer finger to twist the needle and refine the hole.
9) Notice that the hole has a slight fray around the edges. We will want to get rid of this as it obstructs the optics when we are taking a photo.
10) Take a 150 + grit sandpaper and lightly sand down this fray for an even and smooth hole.
11) Tear off at least 2in strips of your gaffers or duct tape to cover the edge of the cardboard to the body of the camera ( be careful that it is not to sticky so as to avoid leaving a residue on camera - you can do this my tearing your strips from the role and lightly adhering and then pulling them off your jeans or carpet first )
12) Attach these pieces to your cardboard so it will be quick and easy to adhere the pinhole once you have taken off the lens of the camera *note you can attach the pinhole directly over the lens but the point of this exercise is to show how light and image works in its most simple form as a camera obscura*
Step 3: Adhere and Setup Your Digital Pinhole Obscura for Taking Photos
1) Make sure your lens is capped and you have a clean place to put it when you take it off.
2) Press the lens release button on your camera and gently turn counterclockwise to release set on a clean paper towel or lens case away from all dust and particulates.
3) Attach the pinhole cardboard cutout with the tape pieces to the body of your camera so that the cardboard is flush against the camera body.
4) Look at the profile of the cardboard and camera body and if they are not flush add additional tape to the other edges of the cardboard.
5) Mount your camera if to your tripod ( this is not done first because you can easily topple your tripod over and damage your camera during the this step )
6) If you have an LCD screen you can set it to preview mode or swivel it around so that you can see the exposure for your images.
Step 4: Compose Photos and Experiment With Light Exposure
1) Gather the materials you would like to photograph if you want to stage a photograph.
- objects that vary in size, texture, and transparency are good to experiment with.
- a bright light ( we used a 10,000 lumen daylight bulb but that is not necessary )
2) Look through the camera with your digital preview feature to see if the placement of your pinhole is correct and tweak as necessary to center your pinhole.
EXPERIMENT
3) Take an image with at least a 5 second exposure time and see what happens ( remember you can't control your f-stop, which is around f/330 )
4) Depending on your result, which will vary based on the intensity of your lighting and the ISO ( digital equivalent of film speed ) your will need to tweak your settings to get a good image ( REMEMBER YOUR SENSOR CANNOT REGISTER THE EXTREMELY HIGH F/STOP SO DON'T USE IT AS A GUIDE.
5) The images we tried out were with moving subjects such as
-The profile portrait by the light, which was a 5 second exposure, 400 ISO.
-The still life using amethyst crystal, modular geometric toys, and film transparencies was an image we created to illustrate how the almost infinite depth of field can compress objects of many sizes to look like they are a similar scale. We also added transparent plexiglass to try added other variables to our photograph and see how longer exposure times changed the color and intensity of the light but not the focus of our images.
- The still photos out of my apartment window which are slightly blurry were taken at midday without any lens on the camera ( they are blurry because the length between my digital camera and where I put the cardboard is too small - this is also known as the focal length and will not be a factor if you attach the cardboard to your lens rather than the camera itself but both are worth trying.)
6) Be ~~~~ P~A~T~I~E~N~T = ) there is a lot of trial and error required in pinhole photography but once you have a good setup you will be able to get great shots.
