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macrumors member
Original poster
May 1, 2019
Hey there,

I have an iMac late 2020 which from their support website should support HDR and Dolby Vision. I also have an iPhone 13 pro which shoots Dolby Vision Videos.

I am a bit confused now

If I playback a video on YouTube in Safari I only get to see the video in 4k but no HDR. If I open the same video on Chrome. I get to see the video in 4k HDR.

Is there any shortcut or anything to display something that the content u are currently watching is HDR or Dolby Vision. Like on LG Tvs if I playback HDR or Dolby Vision I get a notification so I know that I am playing HDR.

Because the same issue I have for other stuff on the Mac. Lets say you want to watch Disney+ video that has Dolby vision or a movie bought on iTunes that has Dolby Vision. you never know if you are really watching that movie now in HDR or Dolby Vision.

The list goes on :)

the same thing with videos recorded on my iPhone 13 pro. on the iPhone I see that it says HDR and Dolby Vision. If I transfer the video to my iMac. I don't even know if it is Dolby Vision or not

quite confusing can somebody help here


macrumors 68030
Aug 15, 2020
SF Bay Area
Yes, it is confusing.
In Safari, you basically have to trick YouTube into delivering you the HDR versions:
Safari>preferences>advanced>show develop menu
Develop>User Agent>select something like Firefox-Windows.
Unfortunately you have to reselect every time. Easier just to use Chrome

In YouTube the setting icon will have a red "HDR" instead of "4K".

Otherwise you usually just have to guess if you getting HDR by looking at it.

However, I do have a trick to help you determine if you are watching HDR content:

In System Preferences, Option-click the Displays icon.
To clarify: hold down the Option key when you click on this Displays icon:
Screen Shot 2021-12-06 at 9.47.41 PM.png

This will reveal the hidden option "Allow extended dynamic range" which should normally be checked.

Now, while you are watching HDR content, repeatedly uncheck and check this option. If it is true HDR content, highlights will brighten and dim as you check and uncheck this option. (There is a bit of a lag/transition.)
If it is not HDR, it will not change. At least, that is my experience. Only on the 2020 iMac. (I am using Big Sur 11.6.1; if you are not, then YMMV.)

Note: on the 2020 iMac, although it is true that it "supports" HDR, the display is not a true HDR display. Whites are brighter, but not the same as a true HDR display like the new MBPs. And the blacks are no contest.

The 2020 iMac is a great display. Not so great for movies with a lot of dark scenes, though.

Hope this helps
Last edited:


macrumors member
Original poster
May 1, 2019
thanks for clarification Didn't know that display option click before to reveal the dynamic range option was was checked by default.
I just would wish Apple would release an update that a notifications comes up when you are watching HDR content like on modern TVs.
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