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iPhone HDR video looks washed out when an app ignores its colour tags

Crisp · built in Grand Rapids · published 2026-08-10 · last updated 2026-09-23

Quick answer

It looks washed out because the app showing it is ignoring the file's HDR tags and reading the numbers as ordinary video. We measured it: a frame stored the way an iPhone stores HDR and read as ordinary video tops out at 74% white and loses about an eighth of its colour. Stored as HDR10, it keeps half its colour. The file itself is fine. Open it in an app that reads HDR, or convert it to standard range with a proper tone map.

The same canal scene three times: vivid and correct first, slightly greyer second, and flat, dim and desaturated third. — One frame, three readings. First: the HDR file read with its tags honoured. Second: the same frame stored as HLG, the iPhone's curve, read as ordinary video. Third: stored as HDR10 (PQ) and read as ordinary video. Frame from the phone demo on our home page, itself derived from a CC0 clip on Wikimedia Commons.

What an HDR file actually stores

Ordinary video, usually called SDR, is built around a display whose white is about 100 nits. HDR stores a much wider range, so a sunlit window can be genuinely bright while the room around it keeps its detail. Doing that takes three changes, and the file carries a label, or tag, for each:

A different brightness curve. HDR uses either HLG (hybrid log-gamma) or PQ (the curve behind HDR10) in place of the standard gamma curve.
Wider colour. HDR uses BT.2020 primaries instead of the BT.709 primaries ordinary HD uses. The same red is written with smaller numbers, because the scale reaches further. Our colour space explainer covers this in more depth.
More precision. 10 bits per sample instead of 8, so the longer scale does not band.

Apple says supported iPhones record video in Dolby Vision HDR, controlled by the camera's HDR Video setting. Apple's developer documentation says what that means inside the file, starting with the iPhone 12: 10-bit HEVC with the HLG curve and BT.2020 colour, plus Dolby Vision metadata on top. An app that ignores the Dolby Vision part can still play it as plain HLG.

What we measured

We don't have real iPhone HDR footage we can publish, so we built the test from a clip we can show. We took one frame of the phone demo on our home page, an ordinary SDR frame, and stored it the way an HDR phone stores video: 10-bit HEVC, BT.2020 colour and the HLG curve, lossless, so compression isn't a variable. We did it a second time with the PQ curve, which is what HDR10 files use. Then we read each file two ways. First with its tags honoured, using the same tone map Crisp ships. Then with its tags ignored, reading the numbers as ordinary BT.709 video. Every step used the ffmpeg 8.1.2 that ships inside Crisp 1.0.1353.

Reading	Whites	Average brightness	Colour	Contrast
Original SDR frame	0.975	0.444	0.322	0.215
HDR file, tags honoured	0.975	0.439	0.329	0.213
HLG (iPhone), tags ignored	0.737	0.381	0.288	0.173
PQ (HDR10), tags ignored	0.569	0.364	0.169	0.111

All four columns are on a 0 to 1 scale. Whites is the 99th-percentile brightness. Colour is average saturation. Contrast is how widely brightness is spread (its standard deviation). The first two rows are the check that the test is fair: read properly, the HDR file gives back the original to within 1.1% (RMSE 0.011). So nothing in the file is lost. The washed-out look in the last two rows is produced entirely by the reading.

One limit you should know about. Because the frame started as SDR, it has nothing brighter than ordinary white. Real HDR footage has highlights above that: sun on water, a lamp, a window. This test shows the part of the complaint that affects the whole picture, the grey whites and the flat colour. It doesn't show how a given app handles those extra highlights.

Why HLG fails gently and HDR10 fails badly

HLG was designed for broadcast, where some viewers would have HDR sets and some would not, so the lower part of its curve behaves much like ordinary video. Read without its tag, an iPhone clip still looks roughly right. Its whites land at about three quarters brightness, because HLG puts standard white at 75% of its scale, and it loses about 12% of its colour, because BT.2020 numbers read as BT.709 come out less saturated. That's the mildly grey, slightly dull look people describe as washed out.

PQ has no such fallback. It encodes absolute brightness up to 10,000 nits, so ordinary white sits a little under 60% of the way up its scale. Read as ordinary video, whites come out at 57%, blacks lift from 0.065 to 0.091, and colour and contrast both roughly halve. HDR10 files, common from games, screen recorders and some cameras, look far worse in the wrong app than iPhone clips do.

Where it goes wrong on a Mac

Apple's own Photos and QuickTime Player read HDR tags. The problems start when the clip leaves them:

An editor or player that doesn't read HDR tags, or one working on a standard-range timeline that never converts what it imports.
An upload to a site that strips the tags or re-encodes without them. That's the same mechanism as why video looks worse after uploading, applied to colour instead of detail.
A file sent to a device or app that has no HDR support at all.
A conversion that re-encodes the picture but drops the tags, so the next app has nothing to read.

How to fix it

Pick the one that matches where the clip is going:

Watching it yourself: open it in Photos or QuickTime Player, which read the tags.
Sending it somewhere you don't control: convert it to SDR with a proper tone map, so you decide how it looks rather than the viewer's software.
Stopping it at the source: on the iPhone, go to Settings › Camera › Record Video and turn off HDR Video. Clips you've already recorded stay HDR.
Editing: put every clip in one range before you start. HDR and SDR are stored on different scales, so a grade that suits one is wrong on the other.

What Crisp does with an HDR clip

We measured this on the installed app, version 1.0.1353, with an HLG clip and an HDR10 clip.

Enhance and the editing tools convert to SDR. Enhance, speed, rotate, reframe, crop and fade tone-mapped both clips to standard range and saved them labelled as BT.709, so the next app reads them correctly. Compress did the same with the HLG clip (it declined the tiny HDR10 test clip as already too small to shrink). There's no setting to get wrong, and it happens without a prompt. Before 1.0.1353 (23 September 2026), Enhance produced the same SDR picture but left its curve and colour labels blank.
Convert keeps HDR as it is. Converting MP4 to MOV rewraps the file without re-encoding the picture. The video data came out byte-for-byte identical to the source, so HDR passes through untouched.
Max hasn't been checked with HDR yet. For Max, the generative restore, convert the clip to SDR first.

Converting to SDR is the right default when you don't know where a clip will be watched. It's the wrong one if you're delivering HDR on purpose. Of the lanes we measured, Convert is the one that keeps it.

HDR questions

Why does my iPhone video look grey on my computer?

It is HDR, and the app showing it is not reading the file's HDR tags, so it treats the numbers as ordinary video. Whites come out grey and colour goes flat. The file is not damaged: open it in an app that reads HDR, such as Photos or QuickTime Player, or convert it to standard range with a proper tone map.

Is my HDR video damaged if it looks washed out?

No. Read correctly, the same file returns the original picture. In our measurement the correctly read frame matched the original to within about 1% (RMSE 0.011 on a 0 to 1 scale). The grey look is produced entirely by how the file is read.

How do I stop my iPhone recording HDR?

Go to Settings, then Camera, then Record Video, and turn off HDR Video. New clips are recorded in standard range. Clips you already recorded stay HDR and need converting.

Does converting HDR to SDR lose quality?

It loses range, because a wider brightness scale is being fitted into a narrower one. Highlights brighter than standard white get compressed. Everything up to standard white comes back intact: in our test the tone-mapped frame matched the original to within about 1%.

Can I mix HDR and standard clips in one edit?

Not safely without converting first. The two are stored on different scales, so a grade that looks right on one clip is wrong on the next. Put everything in one range before you start.

Download Crisp for Mac Free to try, one-time $129 to remove the watermark. Runs entirely on your Mac.