Expert processing tips to enhance your astrophotos ASTROPHOTOGRAPHY PROCESSING

Subtract stars to get more from deep-sky data

Avoid distortion while processing by taking the stars out of the picture with free software

A strophotography processing is all about the art of data control and getting the right balance between stretching data to tease out details, without going too far and 'clipping' it. Once the data is overstretched, delicate details are lost, or the image becomes noisy.

Stars are one major obstacle during processing. They limit the extent to which data can be enhanced, as they distort or become bloated. This reduces the desired 'natural' appearance for deep-sky images. Software that can remove stars therefore allows the user to work on all the delicate details, without being hindered by stars. One example is the free software StarNet++. Originally developed as a PixInsight module, it's now available as a standalone program via www.starnetastro.com/download. StarNet++ is compatible with both CCD and DSLR data, and so a popular choice for most astrophotographer toolkits.

Version 2 of the software was released early 2022 and includes a handy graphical user interface (GUI) that makes it more intuitive. This is the version we used to process our image of the Flaming Star Nebula (IC 405). Here we will go through the steps we took to remove the stars using StarNet++ and then use Photoshop to recover a 'stars-only' file which we could reapply to our fully processed nebula at the end.

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