Apple ProRAW Redefines the Meaning of Raw Files

Historically, a “raw” file from a camera has typically been considered the purest form of image a camera can produce, a straight dump of sensor data that leaves a lot of leeway for editing — a digital negative, if you will.

The reality, though, is that even a raw file from a digital camera has contained some elements of a manufacturer’s interpretation through color science and the nature of coding light into pixels. But while that hand has been light in the past, Apple’s new “ProRaw” format on the iPhone 12 Pro and iPhone 12 Pro Max blow that concept out of the water. The heavily processed “raw” files from the phone include all of Apple’s computational science baked right into the file, leading to the question of what a raw file really is.

But for some, such as YouTuber and photographer Lee Zavitz, it might not even matter. The dynamic range and image quality gains shown in his video bring it up to the levels of a “professional mirrorless camera,” as he describes it. That is high praise for a camera that makes phone calls and has a sensor the size of most point-and-shoot cameras of yesteryear.

I kept watching the video, waiting for the catch. He compared standard iPhone raw files from third-party apps (such as Pro Camera by Moment) to the ProRAW format from the Apple camera app built into the phone. Both versions will appear as standard DNG files, but the Apple version will have Apple’s computational imaging parameters baked in. There doesn’t appear to be a way to control the extent of how they are baked in, and it makes sense. Computational imaging is probably hard-wired into the pipeline for the default camera app.

Example after example shows the ProRAW format trouncing the standard raw files when it comes to things such as dynamic range, noise, overall image quality. Shadows lifted in a ProRAW file showed zero (really, zero) noise, while the regular raw files showed plenty of the kind you’d expect from a camera with a really, really small sensor.

However, while throughout the video, things seemed rosy, the catch was revealed at the end — a zoom in of some of the ProRaw photos showed a lot of waxy, painterly patterns in areas of the photos. It’s something I’ve noticed that was always in the default JPG processing for Apple’s files since I’ve had my iPhone 6s, and it was disappointing to see that appearing in the ProRAW files, suggesting that they are not as magical as they seem. I would often prefer the slightly grainier raw files of that old iPhone I had just because they looked less like they had Vaseline smeared over the lens. It’s why I sing the praises of the Pixel series’ photo-processing.

So, can Apple’s ProRaw files really be considered raw files if there’s already so much processing built into the format? Does this change the definition of what should be considered a raw file? Leave your thoughts in the comments below.