Introduction

Webcams are designed to capture multiple short exposure images of subjects, so as to produce moving images. So why try to use webcams for astrophotography?.

If these moving images are recorded as AVI files, then individual static frames can be selected from these files and processed to produce amazingly good static images that are difficult to match by any other means.

By applying simple modifications, webcams can be made to expose for long periods, enabling them to record images of feint objects.

This article describes modifications that I carried out on a Philips SPC900NC webcam to enable it to be used for long exposure astrophotography. The modifications are based on original work presented by Steve Chambers, but also makes use of various practical implementations presented by others. These works are discussed in the section entitled 'Background / References'.

I have included information about computers, hardware, and software needed to use webcams and to enable these modifications. I have also provided some imformation about software needed to process captured images, and references to other sources of information.

Information given in this article is based on my own understanding and experiences as a beginner in the field of astrophotography using webcams. Some advanced topics are not covered, but newcomers should be able to find most of what they need to get started.