Building a 16th Century Portable Camera Obscura (On a Shoestring Budget)

Preface

     I have been fascinated with the idea of cameras obscura for many years. The first one I saw was a dark room with black curtains with a three inch hole cut in them when I was in college. I spent hours in that room watching the people going about their daily lives upside down, totally unaware they were being watched from a pitch black window. A few months ago, I was bemoaning that there was no true place for photography as an A&S entry in the Society for Creative Anachronism, when one of my friends reminded of the camera obscura and how much joy that simple device had given me years ago. It was in that moment I knew I had to build one of my own.

History

     The earliest and simplest forms of the camera obscura can be found in ancient China and Greece. The philosopher Mozi, around 470 BC, is the first individual in recorded history to talk about the most primitive form of camera obscura (a hole in a box or room) as a tool for observing the sun. Both Aristotle and Euclid described the camera obscura as a means of observing the sun and solar eclipses. Euclid's Optics became the foundation for much of the Western research into optical phenomenon.¹

     It is quite probable that the camera obscura was being utilized as an astronomical device during the early Middle Ages by the highly educated. All one would need is access to Euclid's Optics and a little curiosity to create a simple camera obscura for experimentation. In the Western world during the 11^th century, Abu Ali al-Hasan ibn al-Hasan ibn al-Haytham (Alhazen) from Cairo is the first person to be credited with using a camera obscura as an image projection device and to recommend its uses as a drafting aid. His research on the use of mirrors, lenses, and the eye in Book of Optics is considered the foundation of Western optical science. He also is the author of the modern scientific method.² In China, both Duan Cheng Shi (863) and Shen Kuo (1086) describe inverted images being projected with a camera obscura.³

     During the Renaissance, mirrors and lens start being used to enhance the image produced by camera obscura. It is also during this time that we see portable models being developed as tools for aiding artists in drawing from real life.⁴ Leonardo da Vinci was fascinated by both the camera obscura and the eye. It is speculated that he was the first person to add a lens to a camera obscura to obtain sharper images, but it was mathematician Girolamo Cardano who first wrote about doing so in 1550. However, it was Giambattista della Porta who made the use of a lens type camera obscura popular with his writings in Natural Magick.⁵ Porta was famous for his outrageous parties where he would entertain his guests with live projections onto sheets in a dark room using his camera obscura.^{6 7} The actual term camera obscura was coined in 1604 by Johannes Kepler. He documented using a portable camera obscura in 1600, though the exact model of camera obscura he used at that time is unknown, it was known to be something far more complicated than he had previously used.^{8 9}

Design

     While sketches, drawings, and detailed descriptions of larger room type cameras obscura are available from the 16^th century, aside from mention of their existence and usage, very little actual documentation of what a portable camera obscura looks like still exists from that century. They are described as being in either tents or boxes, but what actual mechanics was used simply is not available. The earliest actual description of how one was designed is from 1620 when Lord Woten was visiting Johannes Kepler to give him one of Francis Bacon's books. He wrote a letter to Bacon describing the device as such: “He hath a little black tent which he can suddenly set up where he will in a field, and it is convertible (like Wind-mill) to all quarters at pleasure capable of not much more than one man, as I conceive, and perhaps at no great ease; exactly close and dark, save at one hole, about an inch and a half in Diameter, to which he applies a long perspective-trunke, with the convex glass fitted to the said hole, and the concave taken out at the other end, which extendeth to about the middle of this erected Tent, through which the visible radiations all the objects without are intromitted, falling upon a paper, which is accommodated to receive them; and so he traceth them with his pen in their natural appearance, turning his little Tent round by degrees, till he hath designed the whole aspect of the field: this I have described to your Lordship, because I think there might be good use made of it for Chorography [the making of maps and topographical views]: For otherwise, to make landskips by it were illiberal, though surely no Painter can do them so precisely. (Reliquiae Wottoniae, London 1651, pp. 413-414.)” ¹⁰ While this is about 20 years out of period, it is the first detailed description of a portable camera obscura. More importantly, Kepler writes about using a portable camera obscura as early as 1600 to view an eclipse.

     I propose that some form of what was described in 1620 could have been built before then with knowledge available at the time. The information on the use of lenses to sharpen the cameras image and the use of mirrors to reflect and flip an image was readily available as early as 1558 with the publication of Natural Magick ¹¹ and more concisely discussed by Giovanni Battista Benedetti in 1585.¹² I have built my camera using many of the principles of that 1620 description.

Materials

     While there is little description of the actual materials used to build a tent camera obscura, the physical structure was likely built from wood and black dyed canvas. Though the type of wood in period was likely pine or some other type of light wood, I was on an extreme budget. I built my entire camera for under $40. With the exception of the tent legs, I built the entire camera out of found (free) wood. The legs would have been found wood as well, however the 1x1 found wood poles I had were insufficient to hold up the main camera body in a robust manner. I purchased a 2”x6”x14' board to replace those poles. These poles secured into the main camera using half inch metal posts which started out as ½” thick steel metal bolts. In period, a wood glue made from cheese and lime would have been used. I opted to use modern wood glue instead. Modern wood glue at its base is almost the same thing as period wood glues, however it contains a few extra ingredients which speed up drying and help strengthen the bond. Additionally, I also used wood screws to help secure load bearing areas. For many years I believed the common misconception that wood screws were not period. However, while researching nails for this project, I discovered documentation of the use of wood screws in the construction of a bellows from 1556.¹³ While the tube was likely made using brass in period, a brass tube was way out of my budget, so I built mine using thin wood, wood glue, water and a mold. My lens and mirror are modern. I currently lack the skill set to make my own mirror and lenses. Also, the lead that backed many period mirrors is toxic. I also used modern black paint instead of a period recipe. Because some of my found wood was already painted, period paint would have been insufficient to cover its modern off white analog.

Construction

     As I describe the construction process, please keep in mind this is only the third woodworking project I have done in my life. The prior two were during college were significantly less complex than this project. As I stated before, the majority of my materials I already had or I scrounged from a friend's wood pile or from the scrap box at the Arkansas Regional Innovation Hub where I did most of the building. I spent about a week scrounging free wood, and once I had a decent supply, I designed my camera three separate ways in the 3d software Houdini. This helped me plan out what I was going to build before I got started. In the Middle Ages, this would have been done with pen, paper, and drafting tools; however, since I have not done old school drafting since 2002, I opted for the tool I know best.

     My first step was to cut four 12”x12” squares from ¾” plywood. I did this using both a table saw and a chop saw. I then took a band saw and cut two 9” circles from two of the 12”x12” squares. Then I cut out eight 1.5”x3”x3” blocks using both chop and band saws. I also cut two 10”x12”, one 12”x12”, and one 12”x14” section out of ¼” thick wood composite board as well as nine 12” long pieces of 1”x2” cedar using the chop saw. With all my major pieces cut, I called it a day.

     The next step was to create the tube and tent leg blocks. I created my wooden lens tube by soaking a 1/16” thick sheet of wood in a mixture of one part wood glue to three parts water for a half hour. I then wrapped a three inch pipe with foil. Once the pipe was wrapped, I rolled the soft wood around the pipe, adding wood glue between the wood after the first full wrap of the wood, and taped the whole thing together tight. After the tube was securely wrapped, I glued the eight 1.5”x3”x3” blocks into four 3”x3” cubes and let it all dry for a day.

     Once the glue was dry, I removed the 6” long tube from its mold and created an end cap cut from ¼” scrap board using a drill and skill saw. I had to do this twice because the first one came out too small. I also used the drill and skill saw to cut a hole big enough for the tube to fit though in the two 12”x12” and two 9” diameter boards. The final act for the main body of the camera was to cut 30 degrees off the bottom of the four 3”x3” cube.

     After all the cuts were completed, it was time to assemble the camera. The camera is design to come apart into two separate sections. I assembled the bottom section by attaching the four angled cut 3”x3” blocks to the bottom corners of the 12”x12” board using wood glue and screws. I then glued the two 9” diameter boards together and let them dry for a few hours. Once they were fairly secure, I attached them to the top of the bottom 12”x12” board with wood glue and screws. Finally, I attached the top 12”x12” board to the top of the top 9” diameter board using wood glue and screws. Once the bottom housing was built, I placed the lens tube through the center hole and attached it to the housing using wood glue and (where needed) a conglomerate of wood glue and sawdust. After the bottom section of the camera obscura was completed, I painted both the bottom section and the ¼” thick box walls black and let everything dry overnight.

     The next day, I assembled the top section of the camera obscura by attaching three 1”x2” cedar boards each to the 10”x12” and 12”x12” to create the tops and sides of the upper section using wood glue and screws. The top and side section support boards were then attached to each other also using wood screws. Finally, I attached the 12”x14” back rear support boards of the front and top. This completed the top section which rests on top of the bottom section using an overlap. When assembled The top and bottom sections are secured using simple hook and eye latches. This allows for different lenses to be interchanged within the lens tube housing.

My first set of tent legs used 78” long 1”x1” poles with 3/8” wide bolts screwed several inches into the end and secured with wood glue. I has 1” deep hole drilled into the base of the camera obscura to go in. However, this proved to be insufficiently robust, so I purchased a long 2”x6” board and cut into four 1.75”x2.75”x78” boards using both table and chop saws. I then converted four 5”x½” diameter bolts into chamfered headless bolts using a metal chop saw and a chamfer grinder. These were screwed into the tent poles and secured with wood glue. These proved to be sufficient to hold up the weight of the camera body.

     The final part of the camera to make was the skirt. This was created by sewing five 12” and 58” wide by 80” high trapezoids side by side, with loops to secure to the camera using a rope. Tents from the time period were traditionally sewn together using a sail stitch; however, I opted for a French seam instead to help with light tightness at the joint. The skirt was machine sewn due to time constraints.

1 Cucchiaro, Roberta History of Pinhole Photography - Days of Camera Obscura -https://robertacucchiaro.wordpress.com/2012/10/24/abelardo-morells-camera-obscura-series/

2 Biello, David . The Forgotten History of Muslim Scientists. Scientific American. March 2, 2011. http://www.scientificamerican.com/article/forgotten-history-muslim-scientists/

3 Takeda, Tatsuoki. History of Pinhole Photography - Days of Camera Obscura. http://bonryu.com/atelier_bonryu_e/PH_Salon_1.3.html

4Wencze, Norma. “The Optical Camera Obscura II Images and Texts.” Inside the Camera Obscura – Optics and Art under the Spell of the Projected Image. Wolfgang Lefèvre (ed.) 2007 Max Planck Institute for the History of Science. Page 14

5 Tavira, Torre. “Short Story about the Camera Obscura.” http://www.torretavira.com/en/pdf/cameras_obscuras.pdf

6 Porta, Giambattista della. Magia Naturalis. 1558

7 Horstmanshoff, Manfred. King, Helen. Zittel, Claus. Blood, Sweat and Tears - The Changing Concepts of Physiology from Antiquity into Early Modern Europe. Leiden, Netherlands. IDN Publishing. 2012. Pages 569-570

8Piccolino, Marco. Wade, Nicholas J. Galileo's Visions: Piercing the Spheres of the Heavens by Eye and Mind. Oxford. Oxford University Press. 2014. Page 262

9 Lienhard, John H. “No. 124: CAMERA OBSCURA.” http://www.uh.edu/engines/epi124.htm

10 Wencze, Norma. “The Optical Camera Obscura II Images and Texts.” Inside the Camera Obscura – Optics and Art under the Spell of the Projected Image. Wolfgang Lefèvre (ed.) 2007 Max Planck Institute for the History of Science. Page 22

11 Wencze, Norma. “The Optical Camera Obscura II Images and Texts.” Inside the Camera Obscura – Optics and Art under the Spell of the Projected Image. Wolfgang Lefèvre (ed.) 2007 Max Planck Institute for the History of Science. Page 15

12Steadman, Philip. Vermeer's Camera: Uncovering the Truth Behind the Masterpieces. Oxford University Press. 2001

13 Agricola, Georgius. De Re Metallica. 1556 

Bibliography

Cucchiaro, Roberta. “History of Pinhole Photography - Days of Camera Obscura.” https://robertacucchiaro.wordpress.com/2012/10/24/abelardo-morells-camera-obscura-series/

Biello, David. “The Forgotten History of Muslim Scientists. Scientific American. March 2, 2011.” http://www.scientificamerican.com/article/forgotten-history-muslim-scientists/

Takeda, Tatsuoki. “History of Pinhole Photography - Days of Camera Obscura.” http://bonryu.com/atelier_bonryu_e/PH_Salon_1.3.html

Wencze, Norma. “The Optical Camera Obscura II Images and Texts.” Inside the Camera Obscura – Optics and Art under the Spell of the Projected Image. Wolfgang Lefèvre (ed.) 2007 Max Planck Institute for the History of Science

Tavira, Torre. “Short Story about the Camera Obscura.” http://www.torretavira.com/en/pdf/cameras_obscuras.pdf

Porta, Giambattista della. Magia Naturalis. 1558

Horstmanshoff, Manfred. King, Helen. Zittel, Claus. Blood, Sweat and Tears - The Changing Concepts of Physiology from Antiquity into Early Modern Europe. Leiden, Netherlands. IDN Publishing. 2012

Steadman, Philip. Vermeer's Camera: Uncovering the Truth Behind the Masterpieces. Oxford. Oxford University Press. 2001

Piccolino, Marco. Wade, Nicholas J. Galileo's Visions: Piercing the Spheres of the Heavens by Eye and Mind. Oxford. Oxford University Press. 2014

Lienhard, John H. “No. 124: CAMERA OBSCURA.” http://www.uh.edu/engines/epi124.htm

Agricola, Georgius. De Re Metallica. 1556

Visual Documentation

3d Mockup

Late night tent sewing math. #tent #sewing #cameraobscura #sca #trigonometry

Measure thrice, cut once. Working on the camera obscura. #sca #scalife #woodworking #cameraobscura

Cutting up boards to build my camera obscura... in a kilt. Yeah, I'm that guy. #sca #scalife #cameraobscura #511tactical #kilt

Cutting round pieces of camera obscura with circular saw. #sca #scalife #woodworking #cameraobscura

Most of the cuts for the business end of the camera obscura are done. #sca #scalife #woodworking #cameraobscura

The tube for the camera obscura will be made from this.  #sca #scalife #woodworking #cameraobscura #arinnovationhub

The wood is soaked in a 3:1 ratio of water to modern cheese glue. #sca #scalife #woodworking #cameraobscura

Wood is left wrapped around the mold to dry over night. #sca #scalife #woodworking #cameraobscura

3x3x1.5 blocks glued and clamped to dry over night. #sca #scalife #woodworking #cameraobscura

Completed lens tube with end cap and and intended lens for camera obscura.#sca #scalife #woodworking #cameraobscura

Making holes for the camera obscura. #sca #scalife #woodworking #cameraobscura

30 degree housing for tent legs attached to the bottom of the business end of the camera obscura. #sca #scalife #woodworking #cameraobscura

Now that I have documentation of wood screws going back to 1554, using both wood glue and screws. #sca #scalife #woodworking #cameraobscura

The business end of the camera obscura is coming together. #sca #scalife #woodworking #cameraobscura

Oh no, Mr Bill. The hole is too big!#sca #scalife #woodworking #cameraobscura

Mix sawdust and wood glue to make an aggregate. #sca #scalife #woodworking #cameraobscura

Fill extra space in hole with sawdust/glue aggregate. Problem solved.#sca #scalife #woodworking #cameraobscura

Don't forget to fix the bottom hole with the homemade wood goo. #sca #scalife #woodworking #cameraobscura

Bottom section of the business end of the camera obscura is done. #sca #scalife #woodworking #cameraobscura #arinnovationhub #millertime

Tent poles cut to length for camera obscura. #sca #scalife #woodworking #cameraobscura #arinnovationhub

Top housing is complete for the camera obscura. #sca #scalife #woodworking #cameraobscura #arinnovationhub

Cutting bolts for the camera obscura. A chop saw Fir metal... seriously epic. #sca #scalife #woodworking #cameraobscura #arinnovationhub

Newly cut thicker tent poles for camera obscura. #sca #scalife #woodworking #cameraobscura #arinnovationhub

Burrs removed and slight rough chamfer added to the end of metal inserts for tent poles. #sca #scalife #woodworking #cameraobscura #arinnovationhub

The camera obscura lives! #sca #scalife #woodworking #cameraobscura #arinnovationhub

Camera obscura fully assembled.#sca #scalife #woodworking #cameraobscura #arinnovationhub

The camera obscura works... the projected image just did not photograph well with the phone. #sca #scalife #woodworking #cameraobscura #arinnovationhub