Introduction: Make an Adjustable Pinhole Camera
This instructable shows you how to convert a 60year old analog camera to a pinhole camera with three different pinholes.
Step 1: Get the Camera
First of all you need the camera. Tha agfa clack was introduced in 1954 and uses medium format film. But with a small modification you can also use 35mm.
I chose the agfa clack, because it is robust, cheap and easy to modify. You can get this camera for a few bucks in online auctions.
If the housing is o.k., don't worry about the function. There is nearly nothing that can get broken.
Step 2: Get a Sheet of Aluminium
As a matter of fact, the hole is the most important thing for a pin-hole camera. But a hole would be nothing if there wasn't anything around the hole. :-)
This is a very thin sheet of aluminium. You can get that from a soda-can, a tea candle or something similar.
Step 3: Make a Hole
The key to a good performance of the pinhole camera is the hole.
The perfect hole is done in multiple steps. Do not just punch through, but make a small dent and polish it away. Dent to the other side and polish again. Do it as long as it takes to make a small hole.
Use this calculator for the best hole-size:
http://www.mrpinhole.com/holesize.php
I chose 0.3mm for the smalles hole, resulting in a aperture of 256.
I checked the size of the hole with a lead of a mechanical pencil, which is 0.3mm.
By the way: The makro-pictures were taken with my smartphone where I applied a laser-lens from an old CD-ROM-drive to the camera.
Step 4: Make Another Hole
Now that you have one perfect hole make another one of different size.
I wanted to have aperture 64 and 16.
Therefore I needed one more pin-hole of 1.25mm and used the existing hole that was already there.
An aperture of 16 doesn't make sense if you want to remove the lens.
I also checked these with leads of mechanical pencils or other stuff I found around in the house. 1.25mm is aproximately the size of a rather thick pin.
Step 5: Modify the Camera
Now disassemble the camera and glue the small sheets of aluminium with the holes to the existing aperture selector.
Then I chose to black-out the back side to reduce reflections. Reflections can also be a nice feature, so try it without and if you don't like it, black-out afterwards.
You can use a candle to produce soot. But try it on some crap material first, because if you do it wrong you might destroy the aperture selector.
Step 6: Reinstall the Lens for Extra Sharpness
If you want a real pin-hole camera you surely have to take out the lens. But you can of course leave the lens in an gain some extra sharpness in the pictures. This is what I did, because I wanted maximum sharpness.
Step 7: Try Out the Modified Camera!
I have also taken account of the Schwarzschild-effect.
If you are working with very long exposures of some seconds and longer, the film doesn't react as calculated and you need to double the amount of time to give it the right exposure.
If you used the same appertures as I did, you can use the list below.
Take a lightmeter and measure at f8, then use the list to find the right exposure for your aperture:
| f8 | f16 | f64 | f64+ | f256 | f256+ |
|---|---|---|---|---|---|
| 1/500 | 1/125 | 1/8 | - | 2s | 4s |
| 1/250 | 1/60 | 1/4 | - | 4s | 8s |
| 1/125 | 1/30 | 2 | 1s | 8s | 15s |
| 1/60 | 1/15 | 1s | 2s | 15s | 30s |
| 1/30 | 1/8 | 2s | 4s | 30s | 90s |
The columns with the "+" include the Schwarzschild-correcture.
Runner Up in the
Lomography Analog Photography Contest
Participated in the
Hardware Hacking
10 Comments
Tip 1 year ago on Step 4
Tipp: after you removed the small screw on the bottom of the lens you simply turn the lens housing counter clockwise to remove it.
9 years ago on Introduction
Very cool!
9 years ago on Introduction
Yo-K, as most pointed out, its not purely a pinhole camera. I'd call it "lens assisted pinhole" in a pinch. A pinhole focuses by diffraction where a lens focuses by refraction. Still a fun project, but beware of reciprocity failure.
10 years ago on Introduction
Nice.
But technically it's not a pinhole camera since you put a lens on the pinholes.
It is only a regular analog camera with 3 apertures as there was many 50 or 69 years ago.
10 years ago on Introduction
A pinhole camera, by definition, has no lens.
10 years ago on Introduction
I used an Agfa Clack for World Wide Pinhole Day 2013 back in April, as did several others from various spots on the globe http://www.pinholeday.org/gallery/2013/index.php?formType=list&f_action=refresh&Country=&Province=&City=&groupname=&searchStr=clack My submission is easy to spot as the worst one on the Clack page :(
The Clack's is indeed a great camera for pinhole photography. As you point out, it is rugged and easy to work on. It also takes a big old' 60x90mm image on 120 film, and that with a curved film plane that drops off less at the edges.
10 years ago on Introduction
It looks and works good, :-)
10 years ago on Introduction
As you already noticed in step 6 since lens remains in place this will not be a pin-hole camera, you only reduced the light coming from the lens, and also the shutter time. In your camera the principle to convey light to focus remains the lens refraction. That "pin-hole" is a nice experiment, but I really don't see which benefit it could improve... :-/
Reply 10 years ago on Introduction
Well, the benefit of the very small aperture is in fact a pinhole-like image.
The depth of field is enormously increased. This is what I like about pin-hole cameras.
Second benefit is the long exposure time, which blurs motion in the picture.
I just don't want to limit myself to only one technique.
Reply 10 years ago on Introduction
Yeah, you added a f256 aperture to your camera, but benefits of pin-hole cameras are only that they don't need a lens ;-)
Very wide depth of field and very long shutter time are peculiarities needed to take unusual pictures, I won't associate them to pin-holes. Anyway it's good that you want to experiment new techniques, and that you have been able to modify an old camera which otherwise couldn't be appropriate.