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How to edit a Milky Way RAW photo on iPad or iPhone
To edit a Milky Way RAW on iPad or iPhone, start with white balance around 3900K, raise exposure until the sky has detail, then add contrast, dehaze and a gentle curve to make the core stand out. Treat the sky and the foreground separately with masks, deal with noise last, and keep everything moderate: a night photo overcooks quickly.
This is the workflow for a single-frame Milky Way shot, the kind most people take with a wide lens at ISO 3200 to 6400 and a 10 to 25-second exposure. It works the same on a Mac. The examples use Raw Smith's slider names, but the steps apply in any RAW editor.
Before you start
- Pick a flat profile. In the Profile panel, choose Neutral. A punchy starting point makes it harder to judge the sky's colour.
- Check the file is supported. If the RAW doesn't open, your camera may not be on Apple's list yet. See which cameras work.
- Turn on lens corrections. Wide, fast lenses vignette heavily, which darkens the corners of the sky. Lens Corrections in the Optics panel fixes this where the RAW carries a profile.
Matt Suess, in PetaPixel's guide to finishing a flat, noisy Milky Way RAW, makes the point well: a night-sky RAW always comes home flat and noisy, and you build the picture in the edit without overcooking it. That's the right expectation.
Set white balance first
The camera's auto white balance at night is usually wrong, often far too warm from light pollution or too blue. Set it yourself before anything else, because every colour decision after depends on it.
- In the Color panel, set the White Balance menu to Custom, and drag Temp to about 3900K.
- Nudge Tint towards magenta if the sky looks green, or towards green if it looks pink. Small moves are enough.
- Adjust by eye. You're aiming for a sky that is neither orange nor blue overall, with blue and warm tones mixed through it.
Why 3900K? Ian Norman of Lonely Speck found that white balance converges on about 3900K for most Milky Way photos, and describes the target as "a good mix of blue and orange" (How to process Milky Way astrophotography). Somewhere between 3800K and 4200K covers most dark-sky sites. Near a town, light pollution adds an orange glow low in the frame, and you may want to go cooler. That same guide suggests a useful trick: push Vibrance and Saturation right up so colour casts are obvious, set Temp and Tint, then put both back to zero.
Lift the exposure
In the Light panel, raise Exposure until the Milky Way is clearly visible and the sky is a dark blue-grey rather than black. Then:
- Pull Highlights down a little to keep the core and bright stars from blowing out.
- Raise Shadows only gently. This is where noise lives.
- Set Blacks so the darkest part of the sky is dark but not crushed. On iPad the histogram's clipping warnings help: shadows that go to pure black show in blue. iPhone has no histogram, so check the before and after often.
Add contrast and dehaze
The Milky Way is a subtle brightness difference against a slightly lighter sky. To separate them:
- Contrast: a moderate increase.
- Dehaze in the Effects panel: often the single most useful slider for night skies, because it cuts the haze of airglow and light pollution and deepens the sky around the core. Start around +15 to +30.
- Clarity and Texture: small amounts bring out the dust lanes. Lonely Speck suggests keeping Clarity, Vibrance and Saturation below +50; past that, colour noise and halos appear.
Shape the tone curve
Open Tone Curve from the Light panel. A gentle S-curve does what the Contrast slider can't do precisely: it darkens the dark sky between the stars while lifting the brighter core. In Parametric, lower Darks a little and raise Lights a little. In Point, drag one point down in the lower third and one up in the upper third. Keep it small; a strong curve makes the sky look painted.
Mask the sky and the foreground
The sky and the land need different edits. The sky wants contrast and cool colour; the foreground wants lifting, warmth and stronger noise reduction. Masks let you do both.
A note on Raw Smith's Sky mask at night. Raw Smith's Sky mask looks for sky by what daytime sky looks like: smooth areas of blue, or bright grey and white, running down from the top of the frame. It looks at the photo before your edits. A dark, star-filled sky usually doesn't pass that test, so expect None found in this photo or a patchy selection. On iPhone ProRAW, Raw Smith uses the sky matte the iPhone recorded instead, if the file has one. Don't count on the AI sky for night shots. These work better:
- Linear gradient. Tap New Mask › Linear and drag it from the top of the frame down to just above the horizon. For a flat horizon this is all you need.
- Refine with a brush. Use + to add a Brush over sky the gradient missed, or − to take mountains and trees back out. On iPad, Apple Pencil makes this much easier: once you paint with the Pencil, your fingers only pan and zoom, and pressure controls the flow.
- Or intersect with brightness. Where the land is clearly darker than the sky, ∩ with a Luminance range keeps only the brighter tones of the gradient.
Turn on Overlay to see the mask in red. Then edit the sky mask: a touch more Dehaze or Clarity, slightly cooler Temperature, a small Curve. For the foreground, open the sky mask's ⋯ menu, choose Duplicate, then Invert the copy. Raise its Exposure and Shadows carefully, warm its Temperature a little if the land should feel lit, and add Noise in its Detail group.
Deal with noise
Night photos are the hardest case for noise, and the stars make it tricky: they're tiny, bright points, exactly what aggressive noise reduction removes.
- Try Enhanced. On iOS 27, iPadOS 27 and macOS 27, the Detail panel has an Enhanced switch for cameras where Apple offers its new RAW 9 decoder. It reduces noise while it reconstructs detail, so it tends to keep small stars that ordinary noise reduction smears. See what Enhanced does.
- Global noise reduction, modest. Raise Noise Reduction until the sky's grain calms down, and check at 100% that faint stars survive. Without Enhanced, raise Color Noise until the colour blotches go.
- More on the foreground. The land is usually the noisiest part and the least harmed by smoothing. Use the foreground mask's Noise slider.
- Sharpening last, and lightly. It brings grain back.
For the theory behind this, see How to reduce noise in high-ISO RAW photos.
Finish the colour
- Vibrance before Saturation, and not much of either.
- In the Color Mixer, the Blue band's Luminance darkens the sky, and the Orange and Yellow bands control the warm glow of the core and any light pollution.
- Color Grading can push the shadows a little cooler and the highlights a little warmer, which reads naturally at night.
- Plane trails and the odd hot pixel can go with Heal in the Remove tab. Spots are circular, so cover a long trail with a row of overlapping spots.
How Raw Smith fits
Raw Smith is a RAW editor and library for iPhone, iPad and Mac. For Milky Way photos it gives you a full single-frame workflow on the iPad: custom white balance in kelvin, a parametric and point tone curve, gradient, brush and luminance masks with their own curve and noise reduction, Apple Pencil for masking, and Apple's Enhanced decoder where your system and camera support it. The masks guide covers each mask type.
What it doesn't do: no star stacking, no star alignment or tracking, no generative remove, and no separate sky replacement. For stacked images, stack on a computer and finish the result there, or try bringing it in as a DNG if your stacking tool writes one; whether it opens depends on Apple's decoder reading that DNG. It's a free download with a free tier and a 14-day trial; Pro is a one-time purchase or a yearly plan. Try it in the public beta on TestFlight.
Questions
What white balance should I use for the Milky Way?
Around 3900K is a good starting point, with Tint adjusted by eye. The aim is a neutral sky with a mix of blue and warm tones rather than a uniformly orange or blue one. Adjust from there by eye, especially if there's light pollution.
Why does my Milky Way RAW look flat and grey?
Because a RAW is developed with gentle contrast and the night sky is a narrow range of dark tones. You build the picture by setting white balance, raising exposure, then adding contrast, dehaze and a curve to separate the core from the sky around it.
Can you edit astrophotography on an iPad?
Yes, for single-frame Milky Way photos. Any iPad that runs a RAW editor can do white balance, curves, masks and noise reduction. What an iPad app generally won't do is star stacking or tracking, which still needs desktop software.
How do I reduce noise in a Milky Way photo?
Expose as brightly as you can in the camera, use a decoder with strong noise reduction such as Apple's RAW 9 where your camera supports it, and add extra noise reduction to the foreground and dark sky with masks, keeping the stars crisp.
Does an AI sky mask work on night photos?
Often not well. Sky detection is usually trained or tuned on daytime skies. For a night sky, a gradient from the top of the frame to the horizon, refined with a brush or a brightness range, is more reliable.