When MobileHDR is disabled in a packaged AR project for iOS there is a big constrast with the brightness in the image and constant screen tearing. This is happening specifically with images captured through the camera at runtime.
I wasn't able to test with 4.25 Preview 1 or 4.26 Main, see this ticket.
Found in 4.24.3 CL#11590370
Reproduced in 4.23.1 CL#9631420
1. Create a template handheld AR project.
2. Setup up project to build for iOS.
3. Launch on the device, unplug it and look at something that has light and shadow in the shot.
4. Disable mobile HDR in Project Settings.
5. Launch on the device, unplug it and look at something that has light and shadow in the shot.
Result: The image has a big contrast in brightness and constant screen tearing.
Expected: The image isn't screen tearing and has expected brightness levels.
There's no existing public thread on this issue, so head over to AnswerHub just mention UE-90099 in the post.