How to turn your DSLR into a Digital Pinhole Camera

The post How to turn your DSLR into a Digital Pinhole Camera appeared first on Digital Photography School. It was authored by Adam Welch.

For all the advances made over the last 190-some-odd years of photographic history, at its primordial core, a camera is a highly simplistic apparatus. Our cameras are just light-proof boxes except for an opening that allows a small amount of light to enter. Any photograph ever made owes its creation to the technology of the camera obscura, from the Latin words meaning “a dark box” or “a dark room.” These magical devices project images consisting of light rays which pass through a singular, relatively small opening (aperture), thus casting the inverted scene inside the darkened space. If you were to add an optical element (lens) and an image receptor (digital sensor, film, other material) then, my friends, you have yourself an essentially modern camera system.

Even today, some cameras operate without lenses, relying only on the raw essentials of image-making to produce a photograph. These are “pinhole cameras” and consist of the bare-bones of photo-making – a light-proof box with an aperture and an image receptor.

A pinhole camera is, in fact, so easy, so simple, that you can morph your current DSLR or mirrorless digital camera into a surprisingly efficient pinhole camera. You can do so, using only a few basic materials that you likely already have on hand.

Not only is making your own digital pinhole camera a great project for all ages, but it is also an excellent way to “reset” yourself if you’ve become a little burnt out with your current photography gear.

For lack of a better phrasing, using a pinhole camera is arguably the most “pure” form of photography you can practice, in terms of tools involved. Let me show you how to turn your DSLR into a pinhole camera.

What you’ll need

As with most things, you can make your digital pinhole camera as simple or as complicated as you would like. For this example, I’m going to show you the most basic construction method I have used thus far. Now, let’s get down to business.

Materials:

• An interchangeable lens digital camera. Although there is little chance of damaging your camera, I still recommend using a camera that you don’t rely upon daily. The reason being that you will have a small opening in which dirt or moisture could enter your camera. For our example, I’m using the back-up for my back-up; a Canon 7D MK1.
• Aluminum foil
• A pin or thumbtack
• Tape. Preferably opaque such as electrical or gaffers tape
• Scissors

That’s it! Yes, really. This is the basic materials that you need to turn your camera into a digital pinhole camera.

A brief introduction to pinhole photography

Before we continue, let’s take a quick time-out to talk about a few of the basic principles of pinhole photography. First of all, this is not going to be a tutorial for making a perfect digital pinhole camera.

Believe it or not, although incredible lacking complication, pinhole photography is an extremely nuanced craft. There are formulas for figuring out the optimum aperture size (the pinhole), and how to determine the actual F-stop you will be shooting to calculate exposure.

Even though we’ll be forgoing the complexities, it’s still good to have grounded knowledge in the principles of pinhole photography before you start.

Focal length

For our purposes, the focal length of your pinhole camera will be practically equal to the focal flange distance (FFD) or your camera. The FFD is just a fancy way of saying how far it is from the lens mount of your camera to the image sensor plane. Most cameras will have a symbol that demonstrates the image plane location.

Check out this handy database over on Wikipedia for finding the FFD for your particular camera. In our case, the FFD is 44mm, which is also our effective focal length. This will come into play when we learn about optimal aperture size for the pinhole camera; which we’re about to talk about right now.

Optimal aperture (pinhole) size

Believe it or not, there is a beautifully elegant equation derived by none other than Joseph Petzval which helps us to determine the best size for the opening of our pinhole camera based on the focal length. In our case the FFD, and the wavelength of light. The equation is as follows:

In the formula “d” is the diameter of the pinhole, “f” is the focal length, and lambda (the “l” with a kickstand) is the wavelength of light. Unless your goal is to make an extremely precise pinhole camera, you can essentially forgo all of the information in this section. Still, if you’re a camera nerd like me, it’s cool to know.

So, based on our formula, my “optimum” pinhole diameter is about .011mm, which is TINY. In fact, if we were to manage it, our effective aperture at 44mm focal length would be about F/157. Again, this is all just food for thought, and it won’t actually play into our final pinhole. You won’t need to crunch any numbers to turn your DSLR into a digital pinhole camera. So let’s move on to the good stuff!

Putting it all together

Now, let’s get to making our pinhole camera. As we’ve said before, this will be an extremely simple construct. We’ll begin by cutting out our aluminum foil diaphragm. This is the operable component of the entire system, as it will be what we eventually use to form our pinhole aperture.

Keep in mind that aluminum foil has a shiny side and a matte side. This will come into play later. A piece of foil 3×4 inches (7.6×10.2cm) should be plenty for almost all cameras.

Creating the Aperture

I like to use the front cap for the camera to trace a rough outline for the diaphragm. Just flip the cap over and this will give a good approximation of the front surface of the camera flange. Feel free to trace the outline on either side of the foil. Don’t worry if you don’t have a front cap to use as a guide, cut the foil as best as you can, making sure to leave some overlap.

Throughout the cutting process, try to keep the foil as unwrinkled and flat as possible.

Next, it’s time for our bravery test. We need to make our pinhole now. If you remember from earlier, our “optimum” pinhole size is .011mm. Of course, we won’t be able to achieve this exactly, so the best we can hope for is to make the smallest hole with the tools we have on hand. The pin I’m using has an approximate diameter of .77mm, which is still much larger than our optimum calculated hole size. So we’ll try to make the opening as small as possible using just the tip of the pin.

Lay the foil shiny side up on a semi-firm surface like a cutting board, or in our example, a piece of poster board. Aim for the approximate center of the foil disk and lightly press down with the pin. Don’t attempt to press the pin completely through the disk. Just a small amount of pressure will likely be sufficient to puncture the foil.

And there you have it; our freshly minted pinhole.

From here, it’s just a matter of fixing our new pinhole diaphragm to the front of the camera.

Mounting the pinhole

Center the pinhole diaphragm as close as possible to the lens mount of your camera. Then, carefully tape the foil to the lens flange. I’m using a few pieces of electrical tape. It’s a good idea to use tape that is as opaque as possible and one which won’t leave excessive residue on your camera once it’s removed. Again, keep the foil as flat as you can.

Begin at the outsides of the foil and be sure that the tape seals the diaphragm as tightly as possible. After this, I like to add a few more pieces of tape to the front of the foil for added strength. A delicate touch is required here. Be mindful not to cover your pinhole!

I know it’s difficult to believe, but you’ve just made a pinhole camera!

Tips for shooting with your pinhole camera

As you have likely already assumed, pinhole cameras make use of relatively small apertures. As such, shooting with them will require longer exposure times. So, a tripod will always be a good idea to have on hand for your pinhole work. Furthermore, it will be complicated to compose your images visually. However, this doesn’t mean that you can’t shoot your pinhole camera handheld!

Here are some suggestions for getting the most out of your pinhole camera when shooting with and without a tripod:

• Bump up that ISO. Use the highest ISO you are comfortable with in order to bring the required shutter speed into a manageable range for handheld shooting.
• Forget the viewfinder. While it’s perfectly acceptable to keep the camera held to your eye, it won’t benefit you all that much. Try shooting with the camera in a “waist level” configuration, holding it close to your body for added stability.
• Pinholes love long exposures! Try mounting your pinhole camera on a tripod and lowering your ISO for some great long exposure images. That small aperture is your friend when it comes to super long exposure photography.
• Protect your camera. Remember, you are now shooting without the protection of a lens. Even though the pinhole is extremely small, dirt and moisture can still make their way into the internal components of your camera.
• Be ready to observe any and all dirt present on your sensor. Seeing as you will be shooting at extremely narrow apertures, any specs of dust or dirt on your camera’s sensor will be readily apparent.
• Try a few extra pinholes. There is no rule saying you have to limit yourself to a single aperture. A few additional pinholes can produce some amazing effects. Experiment with different numbers and configurations of pinholes.
• Embrace the blur. By its very nature, pinhole photography is imperfect. Remember that the beauty of working with a pinhole camera stems from the simplistic nature of the method itself.
• Pinhole photography works great in black and white. Converting your pinhole images to black and white can change the entire dynamic of the photo.

Here are a few examples of images I made with my converted pinhole DSLR:

 

These last two images were made after I introduced three additional pinholes…

Ways to improve your pinhole camera

You can make more heavy-duty pinhole apertures using more sturdy materials and by more precisely measuring and cutting your pinholes. Of course, this means additional work and will likely require much more advanced tools. Still, we can make our pinhole camera perform much better through some simple ingenuity.

The best way to up-the-ante of your digital pinhole camera is by adding a bit of flocking to the inside surface of the diaphragm. Flocking is just a way of reducing reflections and glare inside of the camera by darkening the components that might produce these sorts of problems.

Even though we faced the matte side of the foil inward (told you this would come into play), we can still help further reduce the reflections by darkening the inside of the foil. The easiest way to do this is to use a black permanent marker to darken the inside surface of the diaphragm.

This will help to reduce stray light rays that can degrade image quality. An even better solution is to add dark tape to the inside of the diaphragm. This will make for a much more efficient flocking material. If you plan to add tape flocking, it’s a good idea to apply it prior to making your pinhole. Again, leave a small amount of room around the aperture so that the diaphragm remains as thin as possible.

Final thoughts on pinhole cameras

While I was making the images for this article, I realized what might be the greatest benefit of turning your DSLR or mirrorless camera into a pinhole camera; it makes you forget. What I mean by this is that when you use such a simple camera, most of your worries over composition and tack-sharp focus seem to fall away. It’s an odd feeling, really.

What’s more, given the fact that you’re shooting at such small apertures, it produces an enormous depth of field. This means that the entire scene will technically be “in focus.”

At the same time, you know that without the benefit of a lens, the entire photo will simultaneously be less sharp, even dreamlike. When operating under these conditions, it forces us to strip away our pretenses and focus (photo humor) on the core values of our images.

If you’ve never used a pinhole camera before, I hope that this tutorial has shown you that it is incredibly easy to turn your DSLR into a digital pinhole camera. Follow the steps shown here, and you can have a digital pinhole camera in your hands in less time required to read this article.

Have you ever used a pinhole camera? If so, be sure to share your thoughts and images in the comment section below!

Author’s note: While the method shown here poses little risk to your camera, I strongly urge you to only attempt projects such as these using equipment that you wouldn’t mind being damaged. As always, use good judgment and proceed at your own risk.

The post How to turn your DSLR into a Digital Pinhole Camera appeared first on Digital Photography School. It was authored by Adam Welch.

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