Re-discover the Night Sky #3: hot, stuck & dead pixels

Camera image sensors may have faults.

This may result in an incorrect pixel value.

Welcome to the world of hot pixels, stuck pixels & dead pixels!

Re-discover the Night Sky #2: stacking images in Gimp

Stacking time-lapse photos of the night sky allows you to create 'star-trail' images.

It is possible to get good results using Gimp by selecting the appropriate layer mode.

This post also describes how I hacked one of the existing Gimp scripts.

Re-discover the Night Sky: star trails

With an improvement in the weather, I thought I'd try a bit of night-sky photography.

One thing I've never attempted is taking time-lapse photos and then stacking them to produce star trails.

I used a RaspiCam for the photos and Gimp to stack and process them.