PINHE4D - a 35 mm Pinhole Camera
by schlem, published
"Who would believe that so small a space could contain the image of all the universe?" -Leonardo Da Vinci
Designed for 35mm film, and super hackable, the PINHE4D (P4) puts the pure power of the pinhole in the palm of your hand! A secret known to the ancients, and found in the eye of the chambered nautilus: a tiny aperture can render the visible world!
Photos taken by the P4:
I have created a 3D Printed Cameras group on Flickr
The mission is to share and promote open source cameras and related parts, created with CAD applications and 3D printing. Please join and post content!
I've designed and built a few pinhole cameras - it's immense fun, but it can be difficult to duplicate what others have done successfully. Cut-out paper pinhole cameras have been "2D" printed in magazines (see LINKS), but 3D printing offers a substantial improvement over flimsy paperboard construction. I hope you make, use, and hack this camera for your own artistic endeavors.
Goals for this project include:
- fuctional pinhole camera and proof of concept
- simple design / easy assembly
- promoting development of 3D printed cameras
- a hackable open souce photography platform
- a library of (parametric) parts for homemade cameras
- a useful and peaceful application for 3D printing technology
- fun -- Shoot film, not bullets!
Thanks to aubenc for the knurled surface library!
I look forward to seeing how you evolve and iterate the PINHE4D. I plan to add an Arduino-controlled servo to the shutter for accurate exposure timing and a lens board for using optical lenses.
Mostly prototyped in Tinkercad with some OpenSCAD spice: printed in black ABS on a Printrbot Plus at 0.25mm, 2 perimeters, 40% infill (tripod mounts at 70% infill) I found that two perimeters gave me consistent infill, ergo better strength, but 3 perimeters generated interior voids in some walls that might bend and crack. Cracks = light leaks = bad.
This work is licensed under the Creative Commons - Attribution - Non-Commercial license. This license applies only to the files and documents available for download from the Thing Files section of this Thing.
All other related content (photographs, videos, and verbiage such as contained in "Description" or "Instructions" ) are excluded from this license. with all rights reserved, unless specifically available for download This notice constitutes a clarification, not a change, to licensing for this design.
If you haven't explored pinhole photography, I hope this camera catalyzes your interest. Like learning a different language hones your native tongue, pinhole cameras make you a better photographer. A proper tutorial is beyond the scope of this forum, but look to the links at the bottom of this section, and watch for an Instructable soon. Assembly should be obvious from the pictures, and visit my Flickr link for more.
A word about materials: I tried, really, I tried, to make this in colored plastic, but anything but black ABS is too translucent and will ruin your film. Thicker walls could fix this, but the camera would be unnecessarily heavy and material-costly. Besides, black is a time-honored design choice in photographic equipment.
Bill of Materials
--- printed, BLACK ABS ---
- Body plate (camera front and back)
- Shutter plate (extension, pinhole plate, pinhole clamp, shutter plate, shutter blade)
- Knobs plate (two knobs, rewind shaft, rewind bushings, winding shaft, 2 x winding reel)
- Viewfinder (optional)
Every part can be printed without support.
--- non-printed ---
- Pinhole (see discussion and links, below)
- Adhesive-backed BLACK velvet (http://www.rockler.com/product.cfm?page=9852)
- Large and small rubber bands or spring
- Soft foam block
- 1/4-inch nut for tripod mount
- 4 3mm bolts, 15mm (34, 50mm versions, 8mm for 22.5 mm version)
- 4 3mm nuts
- Loctite or similar for shutter bolt
Additionally, you may want the following for finishing and assembling printed parts:
- ABS glue of choice
- Super glue
- Black Sharpie (or similar) to blacken backside of pinhole
- X-Acto knife
- Misc. files
Before constructing a pinhole camera, a few decisions must be made: film size, frame format, pinhole size, and "focal length". The film (35mm) and frame size (24 x 36mm) decisions have been made here, but you'll still need a pinhole situated some distance from your film. Despite copious opinions on making the perfect pinhole, neither variable is really super-critical, but you'll do well to not stray too far from the recommendations.
A pinhole doesn't focus or refract light like a conventional glass lens element; everything in a pinhole photograph will appear focused. Any given pinhole diameter has an optimal distance from the film, a so-called "focal distance". Generally, larger pinholes and shorter focal distances make for faster exposures. Smaller pinholes give greater detail, and longer focal distances effectively magnify the image in the frame. There are three extension sizes for the PINHE4D, 22.5mm, 34mm, and 50mm, sized for 0.20, 0.25, and 0.30 mm pinholes respectively. You can easily geek out to your heart's content if you want (See links for more info). If you build the 22.5mm version, you will need shorter, 8mm bolts to fasten the pinhole/shutter
I used a very thin tapestry needle to make my pinhole, following the instructions in the article from withoutlenses.com. I estimate that my pinhole is approximately 0.25mm in diameter. From the pinhole diameter and the focal distance (34mm), my PINHE4D has an F-stop of 140 or f/140. The Pinhole Designer application will generate an exposure time chart based on your camera specifications and film choice.
A few technical notes about the PINHE4D:
- Tolerances and fit are very tight. Expect to trim and shape mating surfaces with blades and and other sharp tools for a snug light-tight fit.
- Any warping of interior mating surfaces will make your camera leak light and fog your film.
- Lightly scuff any shiny surfaces inside the camera with sandpaper (spools, shafts, etc.) to minimize reflected light.
- The camera back snaps fairly firmly onto the front, but rubber bands and self-adhesive velvet are cheap light-proofing.
- The surfaces of the camera body that the film touches should be covered with the self-adhesive velvet.
- The shutter should move smoothly, yet be firmly held against the pinhole clamp plate by the shutter plate. A dab of Loctite on the bolt will keep your shutter from gradually loosening.
- Glue and clamp the extension on the body front for maximum light-tightness (do you see a theme here?).
- I used a styrene cement to attach the extension to the body, and super glue for securing the film tensioning foam in the body, and tacking the pinhole on the pinhole plate.
- The shutter assembly is designed to come apart for easy pinhole experimentation and replacement.
- There are three slightly differently-sized bushings for the rewind knob shaft, choose the one closest to the size of the hole in the camera body. I had good luck sanding the bushing to a snug fit.
- The film should be tight enough in the loaded camera that you need to manually turn BOTH knobs to advance or rewind the film. A block of soft foam creates enough friction against the spool to maintain the rotational position of the winding knob. I used air conditioner gap-filling foam, cut to fit.
- The winding knob (right side from behind camera) turns counter-clockwise to advance the film. The rewind knob (left side from behind camera) turns clockwise to rewind the film into the cartridge. See the arrows on top of the knobs.
- One rotation of the winding knob corresponds to a nominal one-frame advancement. There is an index mark on the top of the knob for that purpose. The winding spool has a diameter of 12mm which has a circumference of almost 38mm -which is the standard advancement distance for 35mm film cameras. As more film winds on the spool, the effective diameter increases, and the margins between your photos will increase unless you calculate a decreasing rotation of the winding knob. My initial roll of 36 exposures yielded 31 shots before I ran out of film.
- Alternately, (If you maintain even tension on the film) half way through the roll of film, index your advancement based on the rewind knob's rotational position - it will decrease in diameter for the remainder of the roll. More information on accurate indexing:
- when transporting a loaded PINHE4D, a piece of tape across the winding knob holds your film in position.
Some photographic notes:
- Use a tripod or otherwise immobilize your pinhole camera. Exposures of many seconds are not uncommon, and you don't want your image blurred (unless you do).
- The tripod mounting point (you DO use a tripod for your pinhole photography, right?) might interfere with the lower rubber band hooks. You may need to use some kind of spacer to elevate the PINHE4D 1/2 inch.
- The shutter is designed to be held shut with rubber bands. You can snap the shutter open while it is securely mounted on a tripod, or you can remove the rubber bands and manually open and close the shutter for long exposures or self portraits.
- The viewfinder is proportioned to the 34mm extension's angles of view. Line up the inside edges to visualize the outer margins of your photographic composition. Adding some white tape or paint to the inside edges of the box portion creates good contrast, making it easier to see when the sight lines line up.
- I use a light meter to obtain an exposure value (EV) for a given composition. I use that EV to calculate a shutter speed for an aperture of f/22. Using the chart generated for my camera (f/140) by Pinhole Designer, I adjust the exposure to an appropriate interval. If there are wide tonal values in the shot, I may bracket the exposure with faster and slower shots to hedge my bet.
--- LINKS ---
An encyclopedic article with cross references:
A self-described comprehensive pinhole tutorial:
The basics from Kodak - a quick and dirty primer.
Make your own pinhole:
Pinhole Designer - an excellent pinhole design and exposure calulator. The reciprocity failure function is gold. Sadly, Windows only, but worth it.
Mr. Pinhole - More calculators and more links.
Worldwide Pinhole Photography Day:
A paper pinhole camera, 2D printed in a Czechoslovakian magazine, in the 1970's: http://www.pinhole.cz/en/pinholecameras/dirkon_01.html
Books, books, books; Knowledge is power:
A discussion of accurately indexing film in homebuild (120) cameras: