HACKER Q&A
📣 alin23

Is there a way to find the max brightness (nits) of a monitor?


I develop Lunar (https://lunar.fyi/), a macOS app for controlling the hardware brightness of monitors.

One of its hallmark features is Sync Mode: an adaptive brightness algorithm that can keep the brightness synced between multiple monitors.

Because people usually have different monitor models in the same setup, their luminance curves vary a lot, so 100% on one can have the same perceived brightness as 80% on another. Users can account for this variance by adjusting the curve slope manually in Lunar’s settings, or by fine tuning each monitor until all look the same and have Lunar learn from these adjustments.

I’d like to make this automatic, so that people get already synced curves for each monitor. For that I would need the max brightness value measured in nits or cd/m2 for each monitor but my research hasn’t turned up much.

Is there a database containing this type of information that I don’t know of? Or maybe a way to read/extrapolate this data from monitor memory?

Things I have tried:

    - looking in the EDID
    - sifting through macOS I/O Registry data using “ioreg -l -c AppleCLCD2” (on arm64)
    - searching for databases on Google

  👤 brudgers Accepted Answer ✓
Because monitors are hardware -- not software--. without monitor calibration hardware you're just guessing.

A Datacolor Spyder is the typical consumer level start point for profiling monitors.

Good luck.

👤 yellow_lead
Although this isn't exactly what you're asking - if you have a sufficient user base you could see about crowdsourcing this data.