January 2016 – Jim Easterbrook

Correcting vignetting in digital photographs — software

2016-01-26 by Jim

In a previous blog post I outlined how I correct vignetting in digital photographs. In this post I will describe in more detail the software I’ve written to do this. The corrector is part of my Pyctools project and you can download example scripts that use it from my Pyctools-demo project. The picture below shows … Read more

Correcting vignetting in digital photographs — introduction

2016-01-24 by Jim

I recently purchased a budget telephoto lens for my Canon EOS 100D DSLR camera. It’s a 500mm f/6.3 mirror lens, essentially a small Cassegrain telescope. Like many budget lenses it suffers from “vignetting”, i.e. the edges of a photograph are darker than the centre. The EOS 100D camera has built in vignette correction (called peripheral … Read more