Amanda Bernsohn
Christian Cerrito
Eduardo Lytton

Pinhole Painter Camera

Combining the joy of discovery in film photography with the immediacy of digital photography, this digital pinhole camera lets users “paint” the image of a pinhole camera—embracing any beautiful accidents along the way.

http://www.amandabernsohn.com/pinholepaintercamera

Classes
Introduction to Computational Media - Thur (O'Sullivan),Introduction to Physical Computing - Wed AM (Igoe),Introduction to Physical Computing - Wed PM (Igoe)


Two users, a Subject and Photographer, are invited to take a portrait with this device— a pinhole camera outfitted with an array of photosensors that communicates directly with a computer. This array of photoresistors senses the light values of the Subject's image and is on a floating mechanism that can be moved along the x and y axes of the image plane. As the Photographer moves the handle (manually controlling the position of the array), he or she “paints in” the image of the subject. Sensor values are fed into a Processing program that converts this data into a low-resolution image. Old time picture-taking fun, mixed with the immediate gratification of digital still photography of the modern world! Inspired by the happy accidents that occur when taking pictures with the Holga camera, the Pinhole Painter will produce images that are not sharp and that have blips and strange defects due to the subject’s movement and the camera's bare construction. And we will love those happy mistakes!

Background
Before embarking on our project it was important for us to research any similar projects that involved reducing digital cameras to their most basic form. We found some documentation on projects that took existing devices and hacked them or modified them to make "digital pinhole cameras" or "scanning cameras." After further research we found little or no indication of anyone attempting to do what we hoped to do: combining a pinhole camera with a homemade CCD (charge-coupling device) that used the capture method of a scanner.... Taking a little from here and little from there, we hoped to get a better picture of how our digital photo device could work as a whole. We ventured into the waters of optics, computer vision, astronomy (lucky imaging), the physics of light, the history of photography, and how an Etch-a-Sketch works, among other things. Within the realm of digital photography, some of the concepts we flirted with included: CCDs, scanners, camera backs, camera hacking, lenses, and resolution. Our simple goals were to learn the most we could about the basic principles and hardware in photography while having fun in the design, construction, and use of our device. We hope that you can learn from what we learned!

Audience
The Pinhole Painter Camera is a playful device for anyone who enjoys taking digital pictures. It is specially targeted to Photo Enthusiasts who secretly miss the richness of film photography: the joy of watching the image develop on the photo paper before your eyes, of looking through a viewfinder, of not knowing exactly what you were going to get... The Pinhole Painter hopes to regain some of the imprecise magic and mystery of the cameras of days of old.

User Scenario
A Subject sits on a stool or chair in front of our Pinhole Painter Camera. A second volunteer user, our Photographer, operates the Pinhole Painter Camera. Ideally, he or she will wear a bow-tie. Our Pinhole Painter Camera sits atop a wooden tripod and has the look and feel of an old-style Medium or Large Format camera: it is large, boxy and handsome. The Subject will sit in his or her favorite pose, impersonate their favorite actor, or otherwise move their body to reflect their Mood. Meanwhile, the Photographer will move a handle on the back of the camera horizontally or vertically while looking at a screen that displays the movements of his "Photo-Cursor." The image of our Subject and their Mood is captured as a muddy or dark image "painted away" as the image of the pinhole camera is "magically" revealed. After the Photographer is satisfied with his or her artwork, he or she may then print his or her very own Pinhole Painter Portrait.

Implementation
The Pinhole Painter Camera consists of a pinhole camera, constructed mainly of wood, and supported by a tripod. Inside the back of the pinhole camera there is an array of 16 photo-resistors (in a grid of 4 x4) that can be moved along the X and Y axes by way of three linear joints (similar to those in a mechanical printer/plotter; see picture above). The wires for these sensors come out of the back of the camera, run out of a handle into a multiplexer (expanding the maximum amount of analog data inputs possible), and then into an Arduino microcontroller. The microcontroller communicates with a PC-based Processing program that will take the light values from the sensors, compile them into a visual array, reverse the image (as pinhole cameras are upside-down and reversed), and show the image as someone moves the handle with the photo sensor array "cursor" along the image plane. The Processing program will also give the user the option of "freezing" their image and printing it out (by communicating with a nearby printer or by doing a simple "frame grab").

Conclusion
Besides the more obvious lessons from working on this group project (teamwork, how absolutely great our teammates are), we spent many hours trying to understand schematics, sharpening our Processing/code antlers, learning about bit shifting, honing our soldering skills, and many, many hours trying to make friends with multiplexers. We learned a fair bit about sensors, including a few lessons such as "You Get What You Pay For When Buying Photo Sensors" and "Most Ultrasonic Sensors Are Great Sensing Beyond a Foot and a Half." We learned construction techniques and the basics of camera optics. We learned when and when not to compromise on our goals. We learned to keep our heads up-- sheer ignorance of technical issues such as code or knowing how to communicate with sensors would not hold us back. And when we didn't know the answers to something, we could call on the help of those around us with a little more experience. In the end, it was all going to be ok.... And it could still be fun. There IS life after mutliplexers!