Raw SmithBlog
RAW vs ProRAW vs HEIC: what's the difference, and which should you shoot?
RAW is the sensor's data before processing, ProRAW is Apple's DNG that adds the iPhone's own processing on top of RAW-like data, and HEIC is a finished, compressed photo. Shoot RAW or ProRAW when you plan to edit and want room to recover highlights, shadows and colour. Shoot HEIC when you want small files that look good as they are.
At a glance
| Camera RAW | Apple ProRAW | HEIC | |
|---|---|---|---|
| What's in it | Sensor data, unprocessed | RAW-like image data that has already been through some of the iPhone's processing | A finished, compressed image |
| File type | Maker's format: CR3, NEF, ARW, RAF, ORF, RW2 and others, or DNG | DNG | HEIF, saved as .heic |
| Typical size | Tens of megabytes | About 25 MB at 12 MP, about 75 MB at 48 MP | A few megabytes |
| Room to edit | The most | A lot | Limited |
| Needs a RAW editor | Yes | Yes, any DNG-capable editor | No |
ProRAW sizes are Apple's own figures, which put ProRAW at 10 to 12 times the size of HEIF or JPEG.
What is a camera RAW file?
A RAW file records what the sensor captured, before the camera has decided on white balance, contrast, colour or sharpening. Most cameras record 12 or 14 bits per pixel, far more tonal steps than an 8-bit JPEG. Turning that data into a picture, called developing or demosaicing, happens later, in your editor.
That's why RAW is so flexible. The bright sky that looks white on the camera's screen often still has detail in the RAW, and the white balance isn't baked in, so changing it costs nothing. Every camera maker has its own format: Canon's CR3, Nikon's NEF, Sony's ARW, Fujifilm's RAF and so on. On Apple devices, whether one opens depends on Apple's system decoder. See Will my camera's RAW files open on iPhone, iPad and Mac?
What is Apple ProRAW?
ProRAW is Apple's take on RAW for the iPhone. A phone's tiny sensor relies on computational photography: it merges several frames, reduces noise and maps tones scene by scene. A plain sensor RAW from a phone loses all of that and often looks worse than the HEIC. ProRAW keeps the benefits of that processing while storing the result with RAW-like latitude in a standard DNG.
- Which iPhones: iPhone 12 Pro and later Pro models, on iOS 14.3 or later.
- How to turn it on: Settings › Camera › Formats, then turn on Apple ProRAW (on recent iPhones, Apple ProRAW & Resolution Control). Tap RAW in the Camera app to shoot it.
- Resolution: 12 MP or 48 MP. Apple notes that only the main camera at 1× saves 48 MP; other lenses, Night mode, flash and macro shots are 12 MP.
Because it's DNG, ProRAW opens in any editor that reads DNG, as Apple describes in About Apple ProRAW.
What is HEIC?
HEIC is the file extension for HEIF, the High Efficiency Image File Format. It's the iPhone's default photo format, and Apple devices have read it since iOS 11 and macOS High Sierra. It compresses better than JPEG at similar quality, so photos take up less space. Like a JPEG, it's a finished picture: the iPhone has already chosen the white balance, tone curve and sharpening. If you need JPEGs, Settings › Camera › Formats › Most Compatible switches new photos to JPEG, and iOS converts HEIC automatically when it shares with devices that can't open it (Apple: Using HEIF or HEVC media).
How much difference does it make when you edit?
Most of the difference shows in three places:
- Highlights. In a RAW or ProRAW, pulling down Highlights or Exposure often brings back cloud detail. In a HEIC, clipped areas are simply white.
- White balance. RAW stores white balance as a setting, so you can change it freely. In a HEIC the colour is baked in, and big shifts quickly look wrong.
- Shadows and gradients. More bits per pixel means you can lift shadows and stretch skies without banding.
For a well-exposed photo you share as it is, you won't see much difference. For a backlit scene, mixed light, or anything you plan to grade, you will.
Which should you shoot?
- Shoot HEIC for everyday photos, quick sharing, and when storage is tight. It's the right default for most people.
- Shoot ProRAW on a Pro iPhone for scenes you care about: landscapes, tricky light, anything you'll edit. Switch it on for those shots and back off afterwards to save space.
- Shoot RAW on your camera whenever you plan to edit. If you also want instant JPEGs to share, RAW+JPEG gives you both, at the cost of more space.
How Raw Smith handles each format
Raw Smith is a RAW editor. It imports camera RAW files and ProRAW and edits them without ever changing the original. It doesn't import HEIC or JPEG photos; from Photos it takes the RAW behind a photo and skips photos without one.
- Camera RAW is developed by Apple's system decoder. You start from a profile (Standard, Neutral, Vivid, Monochrome or Apple), and noise reduction and sharpening are set during the RAW decode, in the Detail panel.
- ProRAW opens like any other RAW. The Apple profile reproduces the iPhone's own rendering, so the starting point matches what you saw in the Camera app. When you add a Sky mask, Raw Smith uses the sky matte the iPhone saved in the file.
The editing guide covers every panel, and Darken a sky and brighten a subject puts the ProRAW sky matte to work. Raw Smith is in public beta on TestFlight for iPhone, iPad and Mac.
Questions
Is ProRAW the same as RAW?
Not quite. A camera RAW file holds the sensor data before any processing. ProRAW is Apple's DNG format that combines RAW-like latitude with some of the iPhone's own image processing, so it starts closer to what the Camera app shows.
Is ProRAW better than HEIC?
For editing, yes: ProRAW keeps far more highlight, shadow and colour information. For everyday photos you'll share as they are, HEIC is better, because the files are around a tenth of the size and already look finished.
How big are ProRAW files?
Apple says about 25 MB for a 12-megapixel ProRAW photo and about 75 MB at 48 megapixels, which is 10 to 12 times the size of a HEIF or JPEG.
Can I edit HEIC photos like RAW?
You can edit them, but there's much less room. A HEIC has already been processed and compressed, so recovering blown highlights or making big white balance changes shows its limits quickly.
Which iPhones shoot ProRAW?
iPhone 12 Pro and later Pro models, with iOS 14.3 or later. You turn it on in Settings › Camera › Formats.