HDR Optimization

High Dynamic Range (HDR) displays offer greater brightness and contrast than Standard Dynamic Range (SDR) displays. Photos optimized for HDR displays have brighter highlights and more detailed shadows, resulting in an increased sense of realism and greater impact.
Camera Raw already offers related HDR features, such as Merge to HDR, which blends multiple photos to create an HDR photo. However, in previous ACR releases, the rendered results have always been limited to SDR. For instance, the final 8-bit pixel values were always limited to 0 to 255, and the on-screen results were restricted to the standard brightness range of the user interface.
Adobe Camera Raw (version 16.0) now introduces High Dynamic Range Output. With this, you have:

• the ability to view and edit HDR photos on compatible HDR displays.
• the ability to save HDR photos to disk and open them in Photoshop.

System requirements and recommendations

To use the HDR Output feature, you need the following:

• macOS or Windows system
• Supported HDR display. Recommended HDR displays for macOS include:
  • Apple MacBook Pro 14” with XDR display (November 2021 or later)
    
  • Apple MacBook Pro 16” with XDR display (November 2021 or later)
  • Apple Pro Display XDR
• Recommended HDR displays for Windows include VESA Certified DisplayHDR level 1000 or higher.
  
• Graphics processor (GPU) support. To verify, see Determine if Camera Raw is accessing the GPU.
• On Windows, enable HDR in the Display settings. For details, see HDR settings in Windows.
  

Working with HDR Output

When HDR Output is enabled, Adobe Camera Raw (version 16.0) offers the following new HDR capabilities

• An HDR button in the Edit panel for enabling High Dynamic Range photo processing.
• Open and save photos in the AVIF or JPEG XL format.
• Open other HDR formats, such as 10-bit HEIF (.HIF file extension) files from recent Canon, Nikon, and Sony cameras.

Most options in the Edit panel work similarly in SDR and HDR modes. However, they may need different settings for optimal appearance. HDR processing requires Process Version 3 or later.

HDR Display

Camera Raw supports the display of HDR content for the main image view only. This includes side-by-side and split views. However, Camera Raw currently does not support HDR display in other dialogs that display photo content, such as the Merge to HDR, Merge to Panorama, or Enhance dialogs.

HDR Defaults

The HDR button is turned off by default. To enable it by default for supported HDR photos, navigate to Camera Raw Preferences > Raw Defaults > select Enable HDR editing by default for HDR photos.

The supported HDR photos include DNGs created by the Merge to HDR feature, HDR photos captured in Lightroom for mobile (iOS and Android), and HDR HEIF files.

Saving HDR photos

Once you've finished editing a photo in HDR mode, click the Save button to save it to the disk. Make sure to select the HDR Output box in the Color Space section.

Supported non-raw HDR file formats include:

• AVIF
• JPEG
• JPEG XL
• TIFF
• PSD
• PNG

Recommendations

• Use AVIF or JPEG XL for sharing and web applications, such as online web galleries.
• Use TIFF or PSD for workflows where additional HDR work is required, such as compositing.

AVIF and JPEG XL

The new AVIF and JPEG XL format offers several advantages over JPEG, including higher bit depth support and smaller file sizes, making them a great choice for HDR photos. You can use AVIF or JPEG XL for other types of photos as well.

HDR Color Spaces

Camera Raw currently supports three color spaces when editing or saving a photo in HDR mode:

• HDR sRGB (Rec. 709)
• HDR P3
• HDR Rec. 2020

These are HDR-enabled versions of the existing sRGB, Display P3, and Rec. 2020 color spaces. sRGB has the smallest color gamut and Rec. 2020 has the largest.

Histograms and Color Readouts in HDR mode

When editing a photo in HDR mode, the histogram is split into two parts- an SDR section on the left and an HDR section on the right. A vertical gray line between the two parts indicates the standard-dynamic-range white (SDR White) level, the white of the user interface. If the histogram extends to the right of this divider, the photo contains HDR content, and will require an HDR display to show correctly.

The dashed gray vertical lines mark zones above SDR white, in increments of 1 exposure value or f-stop.

When highlight clipping is enabled, the yellow horizontal bars underneath the HDR section indicate HDR ranges that the display can currently show. Red horizontal bars indicate ranges that are beyond the display's current capabilities.

RGB color readouts use 0 to 255 range for pixel components within the SDR range. However, they use the exposure value (or f-stop) convention for values in the HDR range. For example, a value of +0.5 means 1/2 stop above SDR white. This convention applies to both live and sampled readouts. Yellow values indicate pixels within the display's current capabilities, and red values indicate pixels beyond the display's current capabilities.

Lab color readouts are not supported in HDR mode.

Visualizations

The highlight clipping warning indicator (small triangle button in the upper-right corner of the histogram) uses the same color scheme as the histogram's HDR range-yellow indicates highlight areas in the HDR range that is within the display's current capabilities, and red indicates pixels beyond the display's current capabilities.

In addition, the Visualize HDR option provides a color-coded visualization of different HDR ranges, in f-stop increments. To toggle this option, right-click the histogram and select HDR Ranges from the context menu from the context menu, or select the Visualize HDR checkbox in the Light panel.

SDR Preview and Settings

When an HDR photo is viewed on an SDR display, it must be adjusted or tone-mapped to preserve its appearance as closely as possible. The High Dynamic Range section at the bottom of the Basic panel provides additional options for previewing a photo on an SDR display and adjusting its appearance. These controls affect how Camera Raw saves an HDR photo when the HDR Output box is unchecked in the Save dialog. They also influence the appearance of the filmstrip thumbnail in the ACR dialog and for previews in Bridge.

Open in Photoshop and Camera Raw Filter

Opening an HDR photo from Camera Raw into Photoshop automatically sets the Photoshop document to 32-bit depth with HDR color space. You can then use Photoshop to composite the photo with other HDR content. Camera Raw Filter within Photoshop also supports editing HDR photos.

To correctly display HDR content in Photoshop, navigate to the Technology Previews section of the Photoshop Preferences dialog and select Precise color management for HDR display option.

Other Apps

Google Chrome supports AVIF photos and the proper display of HDR photos. This makes it possible to make standard web galleries that contain HDR photos. It is recommended to use Chrome version 116 or later.

Other apps on your macOS system such as Finder, Preview, and Safari may not currently support reading AVIF or JPEG XL photos. Even if they do, they may not support displaying HDR content. The same is applicable to apps on other platforms, such as Windows, Android, and iOS.

Workflow limitations and recommendations

Software support for HDR photos is limited. Currently, you can use the HDR Output feature in Camera Raw to view and edit HDR photos, open them in Photoshop for additional work, and save them to disk in the AVIF format to be viewed in Google Chrome.