John Potter: Creating a Curved Film Plane Paper Negative Camera


John Potter built something seriously awesome – a curve film plane paper negative camera!

“I built the curved plane paper negative camera as I liked the idea of creating images in a cinematic style,” is what John Potter tells us about his camera after a conversation about curved film planes. “Because I was using such a long negative, I needed to have a curved plane negative, so that each part of the negative receives the same amount of light falling on to it. With a flat plane negative, the ends of the negative would not get as much light falling onto them because they are so much further away from the source of light / pinhole.” He continues to state that there are no lenses involved.

The idea of the curved film plane isn’t new. Some photographers have been doing it for years and these days there are patents for curved imaging sensors. They tend to get rid of distortion and help with other problems. So what better way to do this yourself than with a pinhole camera? That’s exactly what John did. Last year, he became really interested in cinematic photography with anamorphic lenses. If you know anything about anamorphic lenses, they sort of stretch the scene out. Plus, it gets expensive. “…I decided to create a pinhole camera which would provide me with the size of image I desired, namely in a 2.5:1 ratio using 4”x10 paper negatives – the Curved plane 4”x10” pinhole camera,” explains John. “More research and revising my mathematics knowledge later, and I had created a curved plane pinhole camera out of foam board which suited my needs.”

For John, this was a match made in heaven. He already really loved pinhole photography. In fact, he started out by just modifying old cameras. He explains:

“My first pinholes were conversions of old cameras using extension tubes until I came across and old Agfa Isola medium format camera belonging to my dad. I removed the lens and used a piece of aluminium kitchen foil with a pinhole in it. After this, I bought a cheap Coronet Ambassador box camera and converted this in the same way, it was a really easy way to make a robust pinhole camera.

As I read more about pinhole camera, I became interested in building my own camera from scratch and researched the internet for ideas. Using the back of an old medium format camera, I built the JP616 around it using foam board and using aluminium kitchen foil to place the pinhole.”

Eventually, him and his wife built their own darkroom and attended classes on how to develop black and white film at home. He currently uses Fomapan 100.

His current prized camera is called the CP410. It’s made out of some plywood and foam board.

The CP410:
Pinhole: 0.4mm in aluminium kitchen foil
Focal length: 120mm (ish)
F300 rounded down to F256
Calculated horizontal field of view 115 degrees
Calculated vertical field of view 46 degrees.

He continues:

“I love the results from the long exposures required of pinhole cameras because I like the idea of trying to capture the passage of time in a single image rather than freezing time in an instant with much faster exposures. Seeing in the blur of a tree’s movement and the flow of water, something we don’t see while we stand and watch in finite detail. Pinhole images seem to have an aesthetic all their own, not completely sharp, but not necessarily completely out of focus. I had also become a little disillusioned with the seeming necessity for pin sharp detail the digital world seems to crave – here was something I could create from first principles to my own liking and satisfaction. I create my own camera, I take the exposure reading from an old light meter I purchased, and adjust this to suit the parameters of my camera. I then develop the film / paper negative and print it to my liking. All my own work!!

Although it might seem quite involved and difficult to use these cameras because of the necessity of working out your own exposures, once you’ve tried it a few times it is really quite easy, you just have a few more things to think about.”

The images he has captured using these techniques can be found on John’s Facebook page

All images by John Potter. Used with permission.