iPhone Duo records slow-motion video at 4K 120 fps or 1080p 240 fps, runs Action mode at up to 2.8K 60 fps and adds a Night mode time-lapse option, according to Apple’s tech specs. Those are the modes that sit below the headline 4K Dolby Vision and Cinematic mode figures, and Apple did not mention them on stage.
This article covers the secondary video modes only. For 4K Dolby Vision at 120 fps, Cinematic mode and Dual Capture, read our guide to iPhone Duo’s main video modes. Everything below comes from Apple’s tech specs page for iPhone Duo unless another Apple source is named.
Key facts
| Mode | iPhone Duo (Apple’s tech specs) |
|---|---|
| Slo-mo | 4K at 120 fps, or 1080p at 240 fps |
| Action mode | Up to 2.8K at 60 fps |
| Time-lapse | Time-lapse and Night mode time-lapse |
| QuickTake | 4K at 60 fps |
| Standard 4K Dolby Vision | 24, 25, 30, 60, 100 or 120 fps |
| Standard 1080p | 25, 30, 60 or 120 fps |
| Cinematic mode | Up to 4K at 60 fps |
| Dual Capture | 4K at 30 fps |
Slo-mo: 4K at 120 fps or 1080p at 240 fps
Apple lists two slo-mo settings for the rear cameras. The higher-resolution option records 4K at 120 fps, and the higher-speed option records 1080p at 240 fps. Played back at 30 fps, 120 fps footage runs at one quarter speed and 240 fps footage at one eighth, so the 1080p setting gives the slower result and the 4K setting gives the sharper one.
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Note that 4K at 120 fps also appears in the standard Dolby Vision list, where Apple offers 24, 25, 30, 60, 100 and 120 fps. The difference is what the phone does with the frames: the standard mode plays them at full speed for smooth motion, while slo-mo stretches them out.
All of these modes run on the 48MP Dual Fusion camera system: a 48MP Fusion Main at 26 mm and f/1.6 with sensor-shift stabilization, and a 48MP Ultra Wide at 13 mm and f/2.2. There is no telephoto lens; the 2x option on iPhone Duo is a 12MP optical-quality crop of the main sensor, and Apple has not said which video modes offer it.
Action mode tops out at 2.8K 60 fps
Action mode is listed at up to 2.8K at 60 fps, which is below the 4K ceiling of the standard, Cinematic, QuickTake and slo-mo modes. Apple’s spec sheet does not explain the lower resolution, and Apple’s product page separately describes the Duo’s video as “ultra-stabilized” without tying that phrase to a specific mode.
What that means in practice: if you want the steadiest handheld footage Apple offers, Action mode is the setting, but you give up 4K to get it. If resolution matters more, the standard 4K Dolby Vision mode with the main camera’s sensor-shift OIS is the alternative. Apple has not published stabilization figures for either.
Time-lapse, Night mode time-lapse and QuickTake
Apple lists three further modes. Time-lapse is standard. Night mode time-lapse is listed separately, which is the low-light variant for scenes such as skylines after dark. QuickTake video is listed at 4K 60 fps on iPhone Duo.
For time-lapse, Apple’s product page also lists 4K time-lapse for iPhone Duo, and Apple’s iPhone 18 Pro press release describes 4K Dolby Vision HDR time-lapse for the Pro. Apple has not said whether the Duo’s time-lapse records in Dolby Vision, so we are not assuming it does.
iPhone Duo vs iPhone 18 Pro: the video modes Apple lists for each
| Mode | iPhone Duo | iPhone 18 Pro |
|---|---|---|
| 4K Dolby Vision | 24 to 120 fps | 24 to 120 fps |
| Cinematic mode | Up to 4K 60 fps | Up to 4K 60 fps |
| Slo-mo | 4K 120 fps, 1080p 240 fps | Apple’s spec extract for 18 Pro we have does not list slo-mo rates |
| Action mode | Up to 2.8K 60 fps | Not in the 18 Pro figures we have |
| Dual Capture | 4K 30 fps | Not listed |
| ProRes | Not listed | Up to 4K 120 fps with external recording |
| ProRes RAW, Apple Log 2, Genlock | Not listed | Listed |
| Spatial video | Not listed | 1080p at 30 fps |
| Front camera | 12MP outer, 4K Dolby Vision 24 to 60 fps; inner 1080p 30 or 60 fps | 18MP Center Stage, f/1.9; video rates not in the figures we have |
The pattern is clear. iPhone Duo matches iPhone 18 Pro on the mainstream modes, adds Dual Capture, and leaves out the professional pipeline of ProRes, ProRes RAW, Apple Log 2 and Genlock. If those matter to you, our iPhone Duo vs iPhone 18 Pro camera comparison and the guide to iPhone 18 Pro’s video features cover the Pro side.
Slo-mo, Action mode and Night mode time-lapse are listed for the rear cameras only. Apple lists no slo-mo or Action mode figures for the outer 12MP camera or the under-display inner camera.
What Apple has not said
- Whether slo-mo, Action mode or time-lapse record in Dolby Vision HDR on iPhone Duo.
- Why Action mode is capped at 2.8K, or any stabilization measurement for it.
- Whether iPhone Duo supports ProRes, Apple Log 2 or 8K in any form. None appear on the spec sheet.
- Slo-mo or Action mode support on the two front cameras.
- How long any of these modes can run before the phone throttles, and storage use per minute.
iPhone Duo pre-orders open Friday, October 16 at 5 a.m. PT, with availability from Friday, October 23. It starts at $1,999 for 256GB, then $2,199, $2,599 and $3,199 for 512GB, 1TB and 2TB. For the rest of the sheet, read our full iPhone Duo specs rundown.
