Re:How hard would it be to display the contents of an image ...
by alexbock on Sunday January 19, 2025 @06:56PM
(#42763430)
> (This is mathematically worse for a reason I don't remember; it causes any picture taken at a concert with blacklights or blue spotlights to look bad.
The iPhone camera sensor is prone to saturating and clipping the blue channel when strong light from a blue LED is in the frame. Once the blue channel clips at the maximum value, a typical HDR gain map won't do anything to restore more nuance to it because they're not designed to add high-frequency detail to a blob of clipped pixels with identical values in the base image.
Re:How hard would it be to display the contents of an image ...
by karlmedley on Monday January 20, 2025 @03:56AM
(#42766463)
Lightroom seems determined not to support HEIC export, even though iOS has trouble with all of Lightroom’s other HDR formats. From my testing:
- JPEG with HDR gain map is not supported
- AVIF and JXL HDR files look fine on initial export, but do not survive being sent anywhere from the Photo Library.
So far I haven’t found a way to export an HDR file from Lightroom and then share it with anyone, iOS or Android.
> I was able to find a reasonable amount of AVIF HDR images, but HEIC HDR is nowhere to be found.
Anything taken by an iPhone camera is an HDR HEIF image… sort of. For backwards compatibility reasons it's an SDR image with an additional attached image called a gain map that HDRifies it. (This is mathematically worse for a reason I don't remember; it causes any picture taken at a concert with blacklights or blue spotlights to look bad. Once you see this you'll never unsee it.)
I believe the very newest Sony cameras can also save HEIF images, however I don't feel like spending $2500 to upgrade my second-to-newest A7 to a newest A7 to find out.
Lightroom also recently added HDR editing so maybe it can export them now?