HDR Photos: Why They Look Off and How to Convert Them

What an HDR photo is

HDR (High Dynamic Range) is a photo with an extended dynamic range. To explain it without jargon: an ordinary shot can only store a limited set of brightness gradations — from black to white on a fixed scale. HDR stores far more, especially at the very ends of the range: in dazzlingly bright highlights and deep shadows.

Why does that matter? The human eye handles a scene of huge contrast — say, a dark room with a bright window — with no problem. An ordinary photo can't "stretch" to cover that scene: either the window whites out, or the room sinks into black. HDR tries to keep detail in both, bringing the shot closer to what the eye sees. On a proper HDR screen it looks striking: highlights truly glow rather than being merely white.

Why it looks off

Here's the root of the issue. An HDR shot is made for a display that can show an extended brightness range — a modern OLED phone, an HDR monitor or TV. But most screens in the world, and nearly all older apps, are SDR (Standard Dynamic Range). They physically cannot show what's recorded in HDR.

When an SDR device receives an HDR photo, it has to "flatten" the extended range into its narrow one. And if the photo is "bare" HDR with no hints, the program does this on its own, to its own taste. Hence the familiar symptoms:

• Blown highlights. Bright areas and the sky turn into washed-out patches with no detail.
• Faded colors. The shot looks bleached, as if sun-faded — sometimes with an unnatural greenish or overly bright cast.
• Dullness. In other cases the opposite: the picture looks gray and flat, with no contrast.

The trickiest part is that the same file looks different across browsers and apps. Each interprets HDR its own way, so predicting the outcome is nearly impossible.

Gain maps: the clever compromise

To make a photo look right on both HDR and ordinary screens, Apple and Google devised an elegant solution — the gain map. It's not magic, just very logical.

A file with a gain map stores two things: a normal SDR image (the regular picture any screen will show) and a separate gain map — a per-pixel instruction for how much brighter each area should be on an HDR display. Then comes the clever part:

• On an ordinary SDR screen, just the base image is shown — clean and correct.
• On an HDR screen, the device takes the base and boosts brightness per the map — producing the glowing HDR version.

That's why a properly made JPG with a gain map is the ideal format for sharing: it looks great in both places. It's how iPhones and many Androids now shoot.

Tone mapping and where it fails

Tone mapping is the process of collapsing a wide brightness range into a narrow one. Roughly, the algorithm decides: "this dazzling highlight on an SDR screen becomes this light gray, and this shadow becomes this dark."

When a photo has a gain map, tone mapping is controlled and precise — the author defined exactly how to collapse it. But when the photo is "bare" HDR with no map, the app applies automatic tone mapping, and that's where it becomes a lottery. Different browsers use different algorithms that all fall short of how the photo was meant to look, and they're exactly what produces the blown-out or washed-out look.

The conclusion writes itself: if it matters that the photo looks the same everywhere, you can't leave the decision to random tone mapping. It's safer to collapse the range once and lock the result in plain SDR.

SDR vs HDR: the difference

How to turn HDR into a normal JPG

If a photo behaves unpredictably, the most reliable move is to collapse it to plain SDR once and for all. Then it will look the same in any browser, document, and in print.

Technically you need to flatten the extended range and discard the gain map / HDR data, leaving a flat SDR image. The easiest way to do this is to convert to a normal JPG or PNG: re-encoding doesn't carry the extra HDR layers over.

If your shot is already a PNG with an extended range, you can normalize it too via the PNG → JPG converter. The full list of conversions is on the all formats page.

Practical tips

• Always flatten HDR to SDR for websites and documents. That rules out the tone-mapping lottery and guarantees one consistent look for every visitor.
• Keep the original. Flattening to SDR is one-way: you can't restore full HDR from a flat JPG. Hold onto the source HEIC/HDR file if you want to keep the effect.
• Don't "fix" blow-out by hand in SDR. If a photo faded because of HDR, the cure isn't a brush but a correct range collapse during conversion.
• Print is always SDR. Printers know nothing about HDR. Prepping a photo for print? Flatten it to a normal JPG first.

By the way, once flattened to SDR the file is also easy to slim down — we cover how to do that without losing quality in our separate image compression guide.