// HDR Glow

Turn an edited photo into an Ultra HDR gain-map JPEG that glows on HDR screens — Chrome on an HDR Mac, HDR phones, Instagram — and looks exactly like the original photo everywhere else.

🔒 Your photos never leave this browser tab. No uploads, no analytics on your images.

Edited photo required JPEG or PNG, sRGB — drop here or click to choose
HDR export optional 32-bit OpenEXR of the same edit, ZIP compression

Preview

HDR result preview

Choose a photo to see a preview.

Only an HDR screen (in Chrome, or the Instagram app) shows the glow — a normal screen just shows the photo.

Glow map

Glow map preview

 

Black = unchanged, bright = boosted.

How to post this, and compatibility notes
  • AirDrop or Files-app the downloaded file to your phone, then upload it from the Instagram app. Don’t send it through WhatsApp first — it recompresses images and strips the glow.
  • Only HDR screens show the glow: Chrome on an HDR Mac, and HDR phones (iPhone, recent Android). Non-HDR screens just show the normal photo — that’s by design.
  • On a Mac, the Preview app needs macOS 15+ to show the glow. Chrome always works, on any macOS version.
  • The optional EXR is only used if it actually contains highlight data brighter than your photo and matches its pixel size — otherwise the glow is synthesized from the photo itself.