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If I take a photo with my iPhone 13 Pro Max camera and view it on the phone screen, bright lights and colors appear very strong and vivid like an HDR movie on an HDR TV. This is controlled by a setting in Settings > Photos > View Full HDR.

However, if I take a photo with my Canon EOS 6D in RAW and export it to my iPhone, I cannot achieve the same effect. I have tried several color profiles like sRGB, Adobe RGB and Display P3.

Even if I overexpose the image in Lightroom before exporting, its still doesn't use the HDR properties of the screen on the iPhone.

Any ideas how to properly export HDR for the iPhone from Lightroom?

Edit: For clarity, I’m not talking about exposure stacking.

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  • You can't upscale an sRGB image to P3. You can artificially push the gamut, but it will never be accurate. "HDR" has two definitions; one achieved by compressing one or several images into a smaller gamut, the other by either using an exiting wider gamut capture [P3], or forcing it like on a PC [which is often completely artificial].
    – Tetsujin
    Nov 28, 2021 at 18:43
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    Ask Apple to document what that option does, how and when? It seems totally unclear how and when this option kicks in but I would expect it to work only with HDR images taken with the iPhone itself and not with imported images.
    – MrUpsidown
    Nov 29, 2021 at 10:31
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    @Tetsujin I'm not upscaling from sRGB. I have 14-bit RAW files from a DSLR. These have no color space until i export them to whatever color space i select. Nov 29, 2021 at 14:03
  • I still suspect you're comparing what a phone will do to 'pretty up' consumer images with what a DSLR will do by default, ie nothing but what you tell it. You're then 'blaming' the profile, when in fact it's going to be the post-pro.
    – Tetsujin
    Nov 29, 2021 at 18:11
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    how do you export the photos to the phone? do you use an 8 bit format like jpeg? i expect that this option only works with higher bit depth formats, possibly only with heif.
    – ths
    Dec 2, 2021 at 16:36

4 Answers 4

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Unfortunately, the short answer to your question is “Lightroom would have to specifically support this, and it doesn’t.”

Your iPhone photos are being saved to a special version of the HEIF format that includes the necessary information to display the photo in HDR mode on your phone. This is not really related to the “prettying up” that phones do, aside from the fact that this processing on your iPhone is targeting this HDR HEIF output format.

Theoretically, a RAW file could also be processed into this same format. A single frame from a modern DSLR/mirrorless camera has the necessary dynamic range for this. Unfortunately, no RAW processing software actually has this functionality. So there’s no good solution to what you want to do today. See also: https://photo.stackexchange.com/a/128947/105572

There are a few poor workarounds you can try if you really want this functionality, but all of them have significant limitations:

  1. There’s an additional HDR display mode intended for the bracketed photos from older iPhones. It has nowhere near the peak brightness of the HDR HEIF format, but since it’s designed to “upconvert” old SDR photos(that come from a higher dynamic range source) it is triggered by a simple EXIF flag. You merely need to use your favorite EXIF editor to insert the EXIF tag “CustomRendered” with a value of “2”. The iOS Photos app will interpret images with this tag as being taken by the bracketed-HDR mode on old iPhones. (The value of “2” indicates “HDR mode, non-HDR copy not saved”. “3” indicates “HDR mode, non-HDR copy was saved” and will behave the same).

  2. There’s a simple iOS app called “Radiance” that can convert/export HDR HEIF images, but it’s rather limited and only accepts photos from your camera roll as input. This is not ideal, an HDR output image should be generated directly from the RAW data using the full dynamic range data, with a somewhat different curve than an SDR photo would have.

  3. You can use HDR video software such as DaVinci Resolve to import all your RAWs and make a slideshow video. This will properly convert them to HDR and work on basically any HDR display…but it’s a video of a slideshow. It’s not a still photo you can browse through. You have to pause the video to prevent it from continuing on to the next frame, cause…you know, its a video.

UPDATE: October 18, 2022. Adobe has released a tech preview of HDR support within their Adobe Camera Raw library. Currently it is not wired up in Lightroom, you can only access it via Photoshop, and even there it's only supported on macOS. It's documented here for now: https://helpx.adobe.com/camera-raw/using/hdr-output.html

This should give an idea about what the eventual Lightroom interface will look like though, and if you have an HDR-capable Mac you can play with it in Photoshop for now.

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  • Any updates to this perhaps? It’s been a couple months and im still struggling. Even if i convert a ProRAW to a 16-bit 300Mb TIFF in Lightroom it loses the dynamic range display capability. The original ProRAW displays properly using the full brightness of the display. Oct 11, 2022 at 11:04
  • I have tried all CustomRendering modes and some do indeed increase the peak brightness, but as you said - nowhere near that of native photos. Actually, if i copy a heic off my phone and run exiftool, there isn’t even a CustomRendered flag. And the funny thing is they are 8-bit! Somewhere there is a „magic bit” telling the Photos app to display the photo using the glorious full peak brightness of the display. Oct 11, 2022 at 12:59
  • Adobe has released a sorta v0.5 of HDR support: helpx.adobe.com/camera-raw/using/hdr-output.html Currently it's not wired up in Lightroom and only works in Camera Raw within Photoshop, and only then if you're on macOS. But it is being worked on!
    – JtheNinja
    Oct 18, 2022 at 16:52
  • As for the magic bit, I believe it's actually an entire "gain map" layer within the HEIF file which gives a per-pixel luminance scale value, vaguely like how the Radiance RGBE format works. It is custom to Apple's own software as far as I know.
    – JtheNinja
    Oct 18, 2022 at 16:53
  • Yes i just noticed this gain map info and thats where i rested my case for now. Hopefully the Adobe stuff will gain traction and HEIF output support as well, otherwise its useless dor iOS. But at least skmething is happening. Thanks for updating! Oct 20, 2022 at 11:22
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It's possible that the difference is the processing the iPhone is doing to its own photos rather than the display settings. It might also be possible that the iPhone is adding data to its own photos that are then interpreted by the HDR display setting and imported photos don't have these hints.

One way to test this is to view both photos on the computer.

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  • I can provide some photos, is anyone with the technical know-how willing to inspect the metadata? Nov 29, 2021 at 14:04
  • Yes, there surely is a „magic bit” added somewhere. The heic files off the phone are all 8-bit, display normally on a computer but use the full peak broghtness on iOS. Oct 11, 2022 at 13:01
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I have done some more research today, turns out that what I'm after is called "EDR" in the Apple world. According to my research, it is enabled by proper EXIF MakerNote information, and unfortunately controlled by a content-specific tonemap "channel".

This allows photos to render normally on SDR displays, but also leverage the extra dynamic range on HDR displays.

Unfortunately, this means that there is no simple "magic bit" to enable. Each photo needs to be properly exported from a 10+ bit source with a hidden tonemap channel. There is no way i know of that will do this. It should be possible to write a Lightroom Classic plugin to do this, but it's beyond my knowledge of Lightroom and EDR.

The alternative way is like JtheNinja said, to use the Radiance+ app on iOS. I hate the fact that the effect is fake - but it still looks gorgeous...

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No version of LR supports HDR at this time. But Adobe has added support to ACR and Photoshop, including the ability to export an HDR AVIF file, which is likely to become a widespread standard (Chrome/Brave already support). Details at https://gregbenzphotography.com/hdr/

However, there is no support to view HDR still images for any iOS web browser at this time. You can view EXR and TIF images as HDR in your photos roll, or create HDR video showing your still images like a slideshow.

It's still early days for HDR, and I expect we'll see a lot more support this year for browsers, editors, etc. There have been many significant developments in the past few months alone.

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