Siril is a serious, free, cross-platform astro-processing suite: deep, scriptable, and capable. It rewards people who enjoy learning a dedicated tool. NightScape Lab trades that depth for one tool inside Photoshop with no learning curve, focused squarely on nightscape astrophotography.
Siril does a lot: registration, stacking, background extraction, color calibration, and scripted pipelines you can rerun across sessions. It's free, it's cross-platform, and for someone who wants full control of a proper astro workflow (and doesn't mind investing time to learn it), it's genuinely powerful. We respect it a great deal; it leans deep-sky, and that's who it serves best. It keeps getting stronger, too: as of 2026, RC Astro's tools run inside Siril, which makes it an even better free hub for deep-sky processing.
| Capability | NightScape Lab | Siril |
|---|---|---|
| Price | $129 once | free |
| Platforms | macOS & Windows | cross-platform |
| Learning curve | low | real, worth it if you invest |
| Runs inside Photoshop | ✓ panel | separate app |
| Focus | nightscapes | deep-sky leaning |
| Landscape dual-stream stacking | ✓ sky + ground | ✗ |
| Sky mask as an editable Photoshop layer (paint + restack) | ✓ | ✗ |
| Lightroom Classic round-trip (auto-import to catalog) | ✓ | ✗ |
| White balance / color calibration | ✓ | ✓ |
| Background / gradient extraction | ✗ not a Lab tool | ✓ |
| Scriptable pipelines | Recipes (one-click replay) | ✓ full scripting |
| Foreground Sky Merge (color-matched) | ✓ | ✗ |
| Star trails included | ✓ five looks | ✗ |
| Delivers a clean linear result | ✓ linear ProPhoto base image | ✓ |
If you enjoy learning a dedicated astro suite and want maximum control, Siril is a superb free choice. NightScape Lab is for the Photoshop photographer who wants a nightscape workflow that's ready to use immediately and never leaves Photoshop. It's a different trade: less configurability, far less setup.
Not across the board. Siril has more depth and scripting, it's deep-sky-strong, and RC Astro's tools now run inside it. NightScape Lab is narrower on purpose: nightscape astrophotography, inside Photoshop and Lightroom Classic, on a clean base image. Siril also covers gradient extraction, which NightScape Lab doesn't attempt. For the landscape job specifically, NightScape Lab is faster to a finished image.
Some people stack or calibrate in Siril and then finish in Photoshop. NightScape Lab's tools are gated to its own signed base images by default (a clear override exists), so you'll get the most out of it when its own calibrated stack produces the base image directly, with the sky mask already in place as a layer.
A nightscape workflow that lives inside Photoshop and Lightroom Classic and hands you an editable base image.
30-day money-back guarantee. If it's not for you, email for a full refund, no questions asked.