Pinhole Designer, software to help build your pinhole camera

Thibaut Alberny · Published: Oct 3, 2021 · Updated: 18 May 2026

Building a pinhole camera is always enjoyable if you like a bit of DIY. There are countless ways to do it using different materials: tin cans, wooden boxes and 3D printing all work well.

Free software created by David Balihar (david.balihar@pinhole.cz)
A toolkit for building a pinhole camera
Download it here for free

Building a pinhole camera is always enjoyable if you like a bit of DIY. There are countless ways to do it using different materials: tin cans, wooden boxes and 3D printing all work well.

Although the physical construction can be quick and simple, a few parameters must be considered to get the best results from your photographs.

The required hole diameter can be calculated using mathematical formulas that are easy to find online.

But there is also a small, easy-to-use program that provides all this information in a few clicks. I used it to design my pinhole cameras. Here are its different capabilities.

Installation

Download the software from its creator David Balihar’s website: https://www.pinhole.cz/en/pinholedesigner/. It installs like other software.

It was designed for Windows; the original article describes installing it on a Mac using WineBottler.

Among other things, the program calculates:
– the optimal pinhole diameter
– the optimal focal length
– the f-number for a given pinhole diameter and focal length
– exposure times for a given pinhole-camera f-number
– the angle of view, with a diagram

Calculating the angle of view

For me, the first step is choosing the angle of view (the third tab). The pinhole camera will normally have a fixed focal length, so this choice is crucial.

For standard 35mm film, for example, enter the dimensions of the light-sensitive area: 24 x 36 mm. Then choose the focal length to obtain the angle of view.

This is easy to picture when you are used to working with an SLR, but more complicated when building for another film format.

I built several 4×5 sheet-film pinhole cameras and wanted them to be very wide-angle. The light-sensitive area is 95 x 121 mm, and I wanted an angle of view of around 135°. The program suggested a focal length of 32 mm.

Calculating the optimal pinhole diameter

With the focal length established, we can calculate the optimal diameter of the pinhole.

Enter the focal length, and the selected formula gives a result: 0.25 mm in my case.

Entering 0.25 mm in the pinhole-diameter field completes the calculation and gives the aperture value: f/128 in my case.

Calculating exposure times

Next, enter the aperture value in the Exposure tab to calculate the corresponding exposure times from a meter reading at f/22.

Reciprocity failure must be taken into account. Different films require different exposure times.

On the right you can see the list of exposure times for Fomapan 100, the film I use most often. With reciprocity correction, the exposure-time curve is exponential rather than linear.