Pinhole Silliness

Week 22

This really is silliness. The subject is an earthenware vessel I bought in Papua New Guinea and I've photographed it with two very different lenses. The version on the left was made with an AF-S Nikkor 24-70mm 1:2.8G ED and the version on the right from a plastic cup bottom with a pinhole punched in it (with of all things a pin).

I made the lens from a Nikon PK-13 extension ring that mates the plastic cup to the camera. The silliness is because I've attached a piece of plastic with a hole in it to one of the better cameras on the market today. I couldn't stand the thought of buying a decent pinhole camera and I didn't have my tools available to build a better one myself. An interesting thing about pinhole cameras is that they hold focus from front to back but aren't very sharp, especially if enlarged. People do use them for artistic purposes, and Lee Frost has some in his book I like. But they really aren't my cup of tea which is why I haven't gone any further than a plastic cup.

The subject is lit the same for both pictures. It is on a curved piece of poster paper to give a smooth background and surrounded with styroform slabs to reflect the light evenly from a single daylight balanced fluorescent bulb.

The photo has a blue cast to it because the cup bottom was blue and some of that light has seeped in. The exposure was in manual mode at 1.3 seconds with ISO set at 200. By back calculating from the other exposure I guesstimate the aperture of the pinhole is f/500 or so. The focal length might be around 35mm or so, just guessing. My hypothesis is that there is an optimal aperture, which would be an interesting experiment. I also think a pinhole with a sharp edge and no burr would make a better picture.

To make it a somewhat better shot I increased contrast in Photoshop by moving the sliders in on Levels. There is no post to the picture shot with the Nikkor lens other than some sharpening after I downsized.

I probably could have found a better subject too but I ran out of time this week. Anyway, after this experiment I am ready to go back to my better lenses....

Idea based on Pin Sharp, pages 88 to 91, in the book 50 Photo Projects, by Lee Frost.