After you've nailed exposure and focus, stacking is the single biggest step up in nightscape quality. Here's why it works, how to shoot for it, and the easiest way to do it now. (Still wondering whether stacking is even worth it? Start there.)
A single Milky Way frame is a fight against noise. To capture faint starlight you push ISO high and open the shutter as long as the stars will allow before they trail. The result records real signal (the galactic core, dust lanes, thousands of stars), but it also records a lot of random sensor noise that looks like colored speckle across the dark sky.
The key insight: the signal (the sky) is the same in every frame, but the noise is random and different in every frame. If you shoot several frames of the same scene and average them, the signal reinforces while the random noise partly cancels out. Stack more frames and the sky gets cleaner, letting you push the edit far harder without the image falling apart into grain.
The rule of thumb: noise falls with the square root of the number of frames. Four frames roughly halves the noise; sixteen frames roughly quarters it. That's why stacking a handful of exposures beats one longer one.
For a landscape Milky Way shot, 15–30 light frames is the practical sweet spot. Below about 10 you still see meaningful improvement over a single frame; past 30 you keep gaining, but the returns shrink and you spend a lot longer in the field. Start with 20 if you're not sure.
Lock your tripod down and don't touch the composition between frames. The sky rotates slightly frame to frame (that's expected and gets corrected in software), but your foreground should be rock steady.
Use full manual: fixed ISO, aperture, shutter, and manual focus. Shoot RAW, not JPEG. You want every bit of the signal for the stack. Take your frames back to back so the sky doesn't drift too far.
At the end of the session, cap the lens and shoot 8–15 dark frames at the same settings. They cost you nothing but time and can clean up hot pixels, especially on warm nights.
Because the sky moves and the land doesn't, a good stack has to treat them separately. Otherwise aligning the stars smears the ground, or holding the ground still smears the stars. Keep that in mind; it's exactly the problem the software below is built to solve.
Traditionally you'd export to a separate stacking app, wait, then re-import and re-catalog by hand. If your nights live in Lightroom Classic and your edits happen in Photoshop, NightScape Lab closes that loop. Select a night's RAW frames in your catalog, lights and darks together in any order, and choose Stack in NightScape. The engine detects which frames are lights and which are lens-cap darks automatically (a quick two-column review dialog lets you fix any guess), runs the calibrated stack, saves the result beside your source RAWs, imports it into your Lightroom catalog automatically, and opens it in Photoshop, ready to finish.
Don't use Lightroom? The panel's Stack tab has two ways in on its own:
The hard part of a landscape stack is that the sky and the foreground move differently. NightScape Lab uses a dual-stream approach driven by an AI sky mask: it registers the sky to the stars for a clean, deep result, while keeping the static foreground unsmeared. That's the piece Photoshop's own Auto-Align and stack modes can't do on a nightscape.
And the mask is yours to correct. It arrives as a real Photoshop layer on the stacked document. If the boundary isn't right along a tree line or a ridge, paint the layer black and white and click Restack with edited mask; the engine re-runs the whole calibrated stack with your version, as many times as you like.
A satellite streak, an airplane, or a cosmic-ray hit only appears in one frame. NightScape Lab runs a two-pass kappa-sigma rejection: for each pixel it looks across all your frames, works out what's normal, and throws out the few values that are wild outliers before averaging. So the trail on one frame simply vanishes instead of leaving a ghost.
The output is a clean 16-bit linear base image you can edit immediately, with correct color and nothing baked in. Once you've got that clean base, finishing the image is the natural next step.
An honest note: stacking software is a crowded, healthy field. Sequator (free, Windows) and Starry Landscape Stacker (Mac) are excellent one-click nightscape stackers, and DeepSkyStacker is a longtime free deep-sky tool. NightScape Lab isn't "better than all of them at everything." It's the option for the photographer who wants to stack and finish the whole image inside Photoshop, keeping control the whole way. Different audience, not a takedown.
If that hands-on, stay-in-Photoshop workflow sounds like you, NightScape Lab does the stack and the finish in one panel: buy once, own it forever.
30-day money-back guarantee. If it's not for you, email for a full refund, no questions asked.