A Calculator for Pinhole Camera Design - by Sroyon

Two main factors determine how a pinhole camera “sees” – that is, whether its angle of view is wide, normal or tele. The first is the sensor size (throughout this post I’ll use ‘sensor’ as a general term for any photosensitive surface, including film, paper or digital sensor). The second is the focal distance (the distance from the pinhole to the sensor). These three variables – angle of view, sensor size, focal distance – are interrelated. In this post, I’ll explain in basic terms (no complex maths) how these variables affect one another. But mainly, I want to share a Excel calculator which I made to help with pinhole design – along with photo samples, to show that it works. So what does this calculator do? Essentially, you can enter any two variables into the calculator, and it will tell you the third. Let’s say you have a box which is 8cm wide (this being the focal distance). And you to load it with 4×5″ sheets of paper or film. The calculator will tell you that the angle of view will be similar to that of a 21mm lens on a full-frame camera – that is, pretty wide. Another example. […]