You call that wide angle?

 

My recent experiences with much longer than usual and a little shorter than usual distances from the pinhole got me wondering about going even wider than the 20mm front, which captures a 113-degree view. The Variable Cuboid is made to accommodate as short a front as 10mm. What is it like going into that frontier? I've actually made one exposure in a 16x20-inch camera that's almost that wide. I decided to take a more modest step and make a 15mm front, which would give a 127-degree angle of view. It took me almost all afternoon. It has a 0.18mm pinhole from my cast-offs, mounted in an extra-wide shutter opening so nothing got in the way.

The only camera I know of this extreme is Zernike Au's Zero 4x5 System, which has three sections so you can use it at several angles. The shortest is 25mm, slightly wider than my new front, but only in one dimension because of its rectangular format.

When I started making 6x6cm cameras, they were 60mm from pinhole to film. Moderately wide angle to a lens user at 53 degrees, it's whoppingly narrow angle in the pinhole community. My reason for avoiding the popular wider angles was because of the inevitable vignetting. The closer the pinhole is to the film, the farther the light has to go to get to the corners and spreads out more than it does in the center. With this 15mm front, it's over twice as far, which calculates out to four stops. If you've ever under or overexposed a roll of film by four stops, you know what a big deal this is. You'll just get the highlights, if any, at the edges, and the center is going to be overexposed.

I always expected, and saw a lot of examples, of bright circles of image which faded to black well before the edge of the frame. This is sometimes considered as seeing the entire projected image of the pinhole. I see it as not using the whole piece of film.

As I built wider and wider cameras, I found that this could be managed to a point. Firstly, by using semi-stand developing, which holds back those overexposed centers from getting too dense. Reducing the contrast when scanning makes sure it captures everything that's in the negative. If a little at the top and bottom of the histogram is lost in that process, it can easily be brought back to the full range. With 16-bit grey scale files, there's plenty of data to get a completely smooth JPEG. Then I quite liberally treat the image locally, dodging any detail in the corners, burning in the middle, switching between the tool's ranges, and recorrecting the brightness and contrast as necessary.

There are still the dark corners directing the eye to the center that is so prized by vignettophiles, but there is also a composition of the whole frame.

How much difference will another 14 degrees make? 

All except two of these are the entire negative, and those two are still wider than the 20mm. 

The entire Sunroom, from just above my head. The camera looks pretty high up, but I could reach it without extending my arm. Some photons make it to the edges, but mostly just the highlights.

It's no trouble exposing the edge if it's bright enough. Another thing illustrated here is how exposure and resolution are degraded because, from the edge, the pinhole appears to be a rather flat ellipse, further reducing its area, and flirting with serious diffraction. I've known about this forever, but it's still kind of a shock to see the actual difference diagramed like this. 

In the center, you can read the titles of the books. The handle and middle lock of the guitar case are nicely rendered, but the nearer one is fuzzy, and the corner is practically cloudy.

A scheme for handling vignetting is to find a scene with a dark center and bright edges. Under the archway with the dining room window to the left and the well-lit mantle to the right, this seemed like that arrangement. However, my poor human brain could not get the fact that the whole side of the house was in the frame.

Exposing for the shadowed side of the backlit arrangement on the lanai seemed like it could fill the frame.

To fill the frame with a close-up, you have to get really close. There was barely room to get my finger between the camera and the squash to open the shutter.

From the island in the middle of State Street, The Oshkosh Northwestern looks like a toy temple on a broad plaza.

Converging verticals are going to be prominent if you tilt the camera up. A rising front didn't seem worthwhile with this device.

The shadowed entrance with the better lit front windows seemed like the right kind of target. Another super wide feature is that any little deviation from perfectly parallel to your subject is going to result in exaggerated converging perspective.

I've never noticed these architects' credits on the First National Bank building. This is one of the cropped images, but only to level that window sill. Any deviation from level is also exacerbated by the wide angle, and I can't abide a crooked composition.

The patio at Beckets.' The last bit of fuzzy roofline at the upper left and the one on the right are parallel!

The white lanai barely makes an impression at the edges, but there's just enough detail to define the planes.

That patient and willing model sitting in for the comically wide-angle portrait. Really makes my already comically large spectacles look big. I should have gotten closer for the funhouse look. The camera was at least 10cm from my nose. That tiny sunbeam saves the left side of the frame from the oblivion of my shadow.

The 15mm front for the Variable Cuboid has a .18mm hand-drilled pinhole. The film was Ilford HP5 semistand developed in Rodinal 1:100.