After shooting some HLG and DLOG landscape footage a couple days ago I could not see any difference in FCPX. MediaInfo showed no difference between the files except for the filename and duration. (Is there a definitive way to tell if an A2s .mov file was shot in HLG or DLOG??)
So today I configured the camera for DLOG and shot a DCS OneShot and other test subjects. That worked fine.

I then tried switching the camera to HLG. It highlighted as if enabled, but upon switching to camera view I saw the zoom icon, which suggested that it was in Normal mode. Checking the camera setting I found it on Normal.  I tried switching to HLG  a few more times , from Normal and from DLOG, but it will not remain in HLG -- instead always reverting to Normal.

The iOS Fly app was updated yesterday (11/4) to 1.5.0, which caused a firmware update to 02.04.2080. Also note that I uninstalled the Fly app, did a full power down of the iPhone, and then reinstalled Fly. No change.

Although I could not see any difference between the earlier HLG and DLOG footage previously, that suggests that HLG was working previously (the footage definitely did not look like Normal footage).

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UPDATE
Clearly this is a bug in 1.5.0, so a despondent iOS user wonders if there is any way to downgrade to an earlier version.

While there is no way to downgrade from the App Store, the video linked below uses iMazing to export an old app as an IPA file from one device, then install it in another. However, the video deals with an app that is no longer in the App Store.  When I tried the same technique, the Library lists Fly v1.5.0, even though the connected iPad Mini has 1.4.8 on it, which is confirmed in the Device tab list of apps.  But iMazing offers no way to "Export .IPA" from the Device tab; only from the Library tab. The resulting exported IPA is v1.5.0.

SO CLOSE!!!  (I post this in case somebody figures out an alternative approach that works.)

This just started happening to me as well. I can select HLG in the Camera menu but it reverts to w/e was previously selected (D-Log or Normal) as soon as I leave that menu.

djiuser_gh6vwPWeyF2t Posted at 11-6 07:04
This just started happening to me as well. I can select HLG in the Camera menu but it reverts to w/e was previously selected (D-Log or Normal) as soon as I leave that menu.

yep, same description.

I connected an iPad Mini with 1.4.8 Fly on it to my A2s controller, and found that HLG stays enabled and works. Is this a bug in the new 1.5.0 iOS release?

Now I realize that the reason I couldn't tell the difference between HLG and DLOG footage is because the camera was reverting back to the last used DLOG! It's nice to finally see the kind of image HLG produces.

This problem has nothing to do with IOS. It is the 1.5.0 Fly app across both platforms including the smart controller that causes this problem.
To my knowledge the Mavic 3 does not have an HLG mode. It simply got broken by adding Mavic 3 support and DJI never executed a proper regression test. Rather disconcerting!

One more comment on HLG especially for Air2s. I have been shooting almost all of my video with the Air2s in HLG mode and post processed it with Davinci Resolve 17.*. The resulting video in HDR10 mode is truly stunning showing truer colors and much better shadow and highlight details. Needless to say, HLG mode is important to me and I am really glad I managed to downgrade my smart controller to 1.4.12 (1430: the last version just before M3 integration).

I am rather disappointed about the Mavic 3 dropping HLG or any other native Rec2020/10-bit color space capture/record method.

djiuser_gh6vwPWeyF2t Posted at 11-6 07:04
This just started happening to me as well. I can select HLG in the Camera menu but it reverts to w/e was previously selected (D-Log or Normal) as soon as I leave that menu.

Same here also. I'm on Android

I have the same issu! DJI can't figure this out 5 one week. There is also issue with 4k resolution, its also broken becouse in 4k you cant digitaly zoom but now you can like is 1080p mode.
So yes, there is 2 big bug in new fly app

Is it just me, or has HLG disappeared from the product page on the DJI site? All I see listed is DLog-M.

JordanRussPhoto Posted at 11-15 21:10
Is it just me, or has HLG disappeared from the product page on the DJI site? All I see listed is DLog-M.

I sure hope they're not dropping HLG. It's incredible and prefer it over DLOG.

Got a reply from DJI support stating that the engineer is aware of it and that they will have a software update as soon as possible to fix it. So we'll see...