How to stack DSLR data in Siril

Easily combine multiple frames to boost detailin your astro photos

- Charlotte Daniels

Creating a detailed astrophotography image typically involves these steps: imaging the target (known as taking 'light' frames); gathering a series of calibration images ('dark', 'flat' and 'bias' frames); using software to stack these images together to remove noise and increase the data signal; and, finally, stretching this data to boost our target's delicate details and making colour and gradient adjustments to perfect the image.

It's quite common to use multiple software programs to carry out the above steps - for example, stacking software followed by specialist processing software to do the rest. However, the free astrophotography processing software Siril is capable of supporting the entire workflow, from stacking data to managing background gradients and colour saturations afterwards. It comes pre-programmed with various scripts designed to automate many functions and even interfaces with other tools, including StarNet and Pixel Math, to perform additional processing steps.

We're going to run through how to stack data in Siril. Stacking is referred to as 'preprocessing' within Siril and occurs right at the start of the processing workflow.