HDR, or High Dynamic Range, is a technology that enhances photo quality by capturing a wider range of light and dark areas, bringing out details that would otherwise be lost. In the past, HDR in camera apps was simulated using tone-mapping, a technique that compresses HDR colors into the smaller SDR color space, which was the only option as displays couldn’t show true HDR.

With the advent of iOS 17, true HDR support has arrived. HDR photos now come in various formats: SDR photos with an embedded HDR gain map for maximum compatibility, in ProRAW or RAW format with high bit depth, or in true HDR formats like 10bit HEIC or 16bit TIFF. These formats allow for extended dynamic range display on HDR-capable devices.

It’s important to note that photos taken in vividHDR camera mode, while capturing a higher dynamic range by merging multiple exposures, are saved in SDR after being tone-mapped and thus are not true HDR.

When viewing HDR photos in ProCamera, you can tell if a photo has HDR information by enabling the EDR button in the photo album. You should see a noticeable difference in the colors and brightness of highlights. Additionally, when exporting photos in the editing studio, you’ll find options to save as ISO-HDR HEIC 10bit and TIFF 16bit.