How to take HDR Screenshots - JXR image format

Click here for the "Actual HDR Thread" to read about what HDR in Star Citizen is: Link

Here is a HDR screenshot crash course

Now that we can play in HDR, people want to share HDR screenshots.

Luckily, it's a thing and it's called JXR.

What are JXR files?

JXR files are JPG XR format, or JPG Extend Range.

JXR stores the HDR luminance data and wide gamut from 10 bit up to 16 bit but are otherwise the same as normal JPGs, as in their quality is lossy. They're around 20-50 MB depending on the captured contents.

If you want to share HDR screenshots, now you know what you need.

Reminder that since HDR isn't supported on Windows 10 besides being able to be enabled and has no calibration function, we will focus on Windows 11. This is also where the HDR viewing apps are, such as the Windows Photos app (for win11) and the HDR + WCG Image Viewer app, in the MS Store.

There are two ways to take JXR screenshots:

• With the Shortcut; Win+Alt+Printscreen.

• Bringing up the Windows Game Bar menu with Win+G, and clicking "capture".

The screenshots are put in Documents\Videos\Captures

We get both a JXR and a normal PNG file per capture

• Obviously, we need to use HDR mode in Windows and have HDR enabled in the game.

• Using the manual method with the Game bar lets you open the Captures folder at the same time.

• With either you save both a JXR file, and a PNG of the same file. The PNG is an HDR-to-SDR conversion, and won't look the same as if you exported an SDR file manually from an app such as the HDR + WCG Image Viewer app.

• You can also use Nvidia Ansel to capture JXR files, but I won't cover that here.

Tidbits

• No browser etc will recognize them because they're massive 20-50 MB files and as far as we know, no browser or website like Imgur supports it yet.

• You can view JXR files in the Windows Photos app or the HDR + WCF Viewer app you find in the MS Store.

• The JXR file luminance is tied to the Calibration App's profile and the captured max luminance.

• If the HDR monitor a JXR is captured on only does 500 nits and that's what was set in the calibration app, the JXR screenshot will be limited to 500 nits. If you then view it on an 800 nits monitor it won't be as bright as that HDR monitor is capable of.

You can see more information in the HDR + WCF Viewer, I've added a screenshot to this thread of it. See where it says "MaxCLL 424 nits", indicating that on the monitor it was taken that 424 nits is the peak captured, while the monitor it's viewed on 800 nits is the detected peak.

Difference from other image files:

• Any PNG or normal JPG you capture is 8 bit and won't show any 10 bit color or luminance besides up-to normal SDR.

• Converting HDR down to SDR simply makes it a normal SDR image.

• SDR means 8 bit color with normal 100-nits mastering.

• Any monitor running SDR that does more than 100 nits is just increasing the brightness of the image, not the range. Most monitors do more than 100 nits, but there is no "fidelity benefit" for it besides being a little brighter and more usable in well-lit rooms.

• It's pointless to "show off" a normal JPG or PNG even if it's exported from a JXR screenshot or taken in-game of an HDR game. These files simply doesn't contain any HDR information. It's like showing 144 fps on a 60Hz monitor, it's just not possible.

Besides that, unless you're on a decent HDR monitor like an OLED the HDR effect will often look washed out as explained in the main thread. On those 1500-2000 nits QLEDs / MiniLEDs it can look good in a bright room ofc, because HDR is about the range of dark-to-bright and wide colors, but OLED is king for the most part.

Did you know?

You can make CIG support 20-50MB JXR image uploads if you ask them really nicely and maybe front some higher image hosting costs.