How to stack Milky Way photos step by step

NightScape Stacker opens RAW and DNG files directly (Sony ARW, Canon CR2 and CR3, Nikon NEF, Adobe DNG, and more) and converts them for you, so you can drop your camera files straight in. If you would rather apply lens-profile corrections first, export your frames as 16-bit TIFF from Lightroom or Capture One at the same settings: same white balance, same lens corrections, no exposure adjustments. Either path preserves the full dynamic range you captured in camera.

Drag and drop your exported TIFF files into NightScape Stacker. It reads the EXIF data from each frame and checks for consistency. If frames were shot with different ISO settings, shutter speeds, or lenses, it will flag the mismatches before you start. This matters: stacking incompatible frames degrades the result instead of improving it.

NightScape Stacker aligns each frame to compensate for Earth's rotation between exposures, then combines them using sigma-clipped mean averaging. The alignment handles the sky independently from the foreground, so your mountain or tree line stays sharp while the stars align correctly. The stacked result has dramatically less noise than any single frame.

After stacking, open the White Balance panel. Auto white balance samples star colors across the frame to compute a correction: stars as a population are approximately color-neutral, so a systematic color shift is what the camera introduced. Astro-modified cameras carry a strong red cast from their extended Ha sensitivity. Stock cameras can also show a color bias from sensor or lens characteristics. Hit Auto, then fine-tune with the temperature and tint sliders.

Open the Denoise panel. The AI model removes sensor noise without softening stars or edges. Start with the Strength slider at around 25% for a clean stack, or push it higher if you shot at high ISO or with fewer frames. The Detail slider protects the sharpest parts of the image: stars, the horizon line, and fine texture. Use the split slider to compare the original and denoised result in real time.

The star removal or reduction tool shrinks or removes stars that are drawing attention away from the Milky Way core. Use the live overlay to see exactly what will change before committing. Adjust the size threshold to target the largest bloated stars without affecting smaller pinpoints. Two modes are available: shrink (reduces star size) and remove (eliminates stars entirely).

The Light Pollution Removal panel corrects both problems at once. Place sample points across the background sky, avoiding the Milky Way and including both the brighter horizon glow and the darker sky above. A correction surface is fit through your points and subtracted: it evens out the uneven brightness from atmospheric falloff and strips the color casts from artificial light, where sodium streetlights leave an orange cast and LED streetlights a blue-white one. A separate surface is fit per color channel, so each cast is removed without flattening the natural color of the sky. The AI sky mask limits corrections to sky pixels automatically.

Export the processed image as a 16-bit TIFF. This preserves the full dynamic range for editing in Lightroom or Photoshop. Open the exported TIFF in Lightroom and apply your tone, color, and exposure adjustments. The stacked and cleaned image responds much better to editing than any single frame, with more shadow detail to pull from and cleaner highlights to work with.