iPhone 18 Pro is the first iPhone with a mechanical aperture you can set yourself. Apple’s tech specs list four stops on the 48MP Fusion Main camera, f/1.48, f/1.8, f/2.8 and f/4.0, and a new Pro controls experience in the Camera app that adds manual aperture, shutter speed, white balance and a live histogram.
This guide covers what each stop does, how to reach the manual controls, and what to check when a shot comes out too dark or too blurred. Apple has not yet published a support article for Pro controls, so the sequence below follows Apple’s description of the feature on its iPhone 18 Pro overview page and the current iOS 26 Camera layout. iPhone 18 Pro ships with iOS 27, and the button names and menu positions may shift slightly once the update lands on September 14.
What the four aperture stops are for
Apple’s overview page pairs each stop with a use case, and the camera picks between them automatically unless you take over. The blades are laser-cut, six of them, and Apple says the widest setting delivers around 50 percent better low-light performance than the iPhone 17 Pro.
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| Aperture | Apple’s description | Typical use |
|---|---|---|
| f/1.48 | Maximum light | Low light, night scenes, the strongest background blur |
| f/1.8 | Default balance | Everyday shots and portraits with natural separation |
| f/2.8 | More depth | Two or three people, street scenes, product shots |
| f/4.0 | Maximum depth | Group photos and landscapes where everything should be sharp |
A wider aperture (smaller f-number) lets in more light and narrows the zone of focus. A narrower aperture does the reverse. Our variable aperture explainer goes deeper on the optics.
How to set the aperture manually
- Open Camera by clicking the Camera Control button or tapping the app icon.
- Tap the controls button, or swipe up from the camera modes at the bottom of the screen, to reveal the adjustment row. This is how the current iOS 26 guide opens Styles and Exposure, and Apple describes Pro controls as living in the same customizable area.
- Select Aperture from the Pro controls set.
- Pick one of the four stops: f/1.48, f/1.8, f/2.8 or f/4.0. The preview updates so you can see the change in background blur before you shoot.
- Tap the Shutter button, or click the Camera Control, to take the photo.
Camera Control offers a shortcut for depth without opening the Pro set. Apple’s Camera Control guide lists a Depth setting that increases or decreases the background blur and switches on Portrait mode if it was off. Lightly press the button twice, slide to Depth, and slide again to adjust.
How to set shutter speed and check exposure
Shutter speed is the second manual control Apple names. A faster shutter freezes motion but needs more light; a slower one brightens a dim scene but blurs anything that moves, including your hands. The histogram Apple added is there to catch clipping before you press the shutter.
- With Camera open, reveal the controls row as in step 2 above.
- Select Shutter Speed from the Pro controls set and drag to the value you want.
- Open the histogram. A graph piled up at the right edge means blown highlights; piled at the left means crushed shadows.
- Adjust White Balance if the scene looks too warm or too cool under artificial light.
- Take the shot with the Shutter button or the Camera Control.
Apple has not published the shutter speed range or whether the manual values persist between sessions. Its overview page only states that aperture, shutter speed, white balance and the histogram are all customizable within Pro controls.
Which stop to pick for common situations
- Night street with no tripod: f/1.48 and let the camera set the shutter, or use Night mode, which still runs automatically.
- Single portrait: f/1.8, the default Apple picks for portraits, with Depth Control available in Portrait mode afterwards.
- Two people side by side: f/2.8 keeps both faces within the focus zone.
- Group photo or a wall of text: f/4.0, then check the histogram for shadows.
- Moving subject in daylight: a faster shutter speed with f/1.8 to keep the exposure up.
If the manual controls do not appear
- The Pro set is missing from the row: Apple describes it as customizable, so it may need enabling in Settings, Camera, once iOS 27 documents the switch.
- Photos look too dark after choosing f/4.0: the narrower aperture needs a slower shutter or more light. Drop to f/2.8 or let the camera manage shutter speed.
- Blur on everything at a slow shutter: that is camera shake rather than depth of field. Brace the phone or raise the shutter speed.
- The aperture options are missing entirely: only the iPhone 18 Pro and 18 Pro Max have the variable-aperture Main camera, and the Ultra Wide and Telephoto lenses keep fixed apertures of f/2.2 and f/2.8.
iPhone 18 Pro deliveries begin Friday, September 18.
