Portrait mode HEIC photos from an iPhone carry more than the final picture you see on screen. Inside the file is a depth map, a grayscale layer that records how far each object is from the camera. Convert a portrait mode HEIC to PNG and the depth map is discarded. Only the rendered image, including the background blur as it looked at the moment of export, is kept. You cannot adjust the blur after conversion because a flat PNG holds no depth data. Edit the blur and lighting in the Photos app before you convert.
What Portrait Mode HEIC Files Actually Contain
An iPhone Portrait mode photo is saved as a HEIF file (the .heic extension on iPhones). HEIF files can store more than one image in a single file. The main image is the final color photo you see. Alongside it, the file can carry auxiliary images. In Portrait mode, one of those is a depth map.
The depth map is a black and white image where lighter areas are closer to the camera and darker areas are farther away. The phone uses that depth map to decide which parts of the photo to blur and by how much. This is the core of the iphone portrait photo depth data that makes the effect adjustable later.
How the Depth Map Controls the Blur
The depth map is not a filter you apply and forget. It is a separate data layer that the iPhone Photos app can read and modify. Open a Portrait mode photo in Photos and tap Edit. You see a Depth (f-number) slider. Move that slider to change the strength of the background blur. The app uses the depth map to recalculate which areas stay sharp and which become softer.
Tap the yellow Portrait button in Edit to turn the blur off entirely. The photo reverts to a standard flat image. All of this works because the HEIC file still holds the original depth map and the original unblurred image data.
What Happens When You Convert HEIC to PNG
PNG is a format designed for a single flat image. It does not support auxiliary image layers or depth maps. When you convert a Portrait mode HEIC to PNG, the conversion process renders the final image as it appears on screen at that moment. It saves only that rendered picture. The depth map is discarded. The converted PNG shows the photo exactly as it was rendered at the time of export, with the blur locked in.
Why You Should Edit Before You Convert
Because the depth data is gone after conversion, any changes to the blur must be made while the file is still in HEIC format. You cannot edit portrait blur after conversion. The blur you see in the PNG is final. The same applies to Portrait Lighting adjustments, which also rely on the depth map. To avoid being stuck with a blur you do not like, follow this procedure:
- Open the Portrait mode HEIC photo in the Photos app.
- Tap Edit and use the Depth (f-number) slider to set the blur strength you want.
- Tap the yellow Portrait button to remove the blur entirely if you prefer a fully sharp image.
- Adjust Portrait Lighting if needed.
- Make any other edits (crop, color, exposure).
- When the photo looks the way you want, convert the HEIC to PNG.
The resulting PNG will match the edited version exactly. There is no way to undo or redo the blur.
Portrait Mode Convert PNG What the Final Image Looks Like
When you complete a portrait mode convert PNG process, the file you get is a standard PNG with no hidden layers. It opens in any viewer or editor. The background blur is baked into the pixel data. If you later want a different blur effect, go back to the original HEIC file and repeat the editing process before converting again. Keep the original HEIC files as a backup.
Practical Tips for Managing Portrait HEIC Files
Keep Your Originals Safe
Keep the original HEIC files if you think you might want to change the blur later. Delete them only after you are certain the PNG version is final.
Sharing With Non-iPhone Users
If you share a Portrait mode HEIC with someone who does not use an iPhone, they may see only the rendered image because other apps cannot read the depth map.
Using Conversion Tools
When you use a conversion tool like heictopng.me, the depth map is not transferred. The tool outputs the flat rendered image.