In iOS automation settings it is impossible to select 2700k colour (the selector ends at 2703k) or to select red colour (left lower corner is impossible to reach).
This is happening only in automations, in device settings it is ok.
This is happening only in automations, in device settings it is ok.
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Hello @martina_zel
Thank you for letting me know, I think the Aqara team will pay attention to this.
These types of smart lights use dual-color-temperature LED mixing, meaning the color temperature is produced by blending warm white LEDs (e.g., 2700K) and cool white LEDs (e.g., 6500K) in different proportions. At the hardware level, color-temperature control is based on mired values. The mired value that is actually sent to the device is then mapped to the nearest corresponding Kelvin color-temperature integer.
So when you expect to set it to 2700K, the device actually selects the nearest discrete value and rounds it, which may end up as 2703K. This is not a bug — it’s simply how the underlying conversion works.
RGB or color-capable lights behave the same way, and are even more complex. Their output is mixed using multiple channels (red, green, blue, and sometimes a white channel), so the final “K value” is also converted from discrete values to the closest integer.
Therefore, with both dual-white and RGB lights, it’s normal to see non-uniform or non-1-step K values — the system is simply choosing the nearest achievable color-temperature value.
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Sorry, my colleague just reminded me that, for example, on the LED Strip T1, and Ceiling Light T1M，the minimum color temperature in Automation is 2703K, while on the device page it’s 2700K. So there is indeed an inconsistency at the moment.
Please rest assured, as I explained earlier, the color temperature is converted from an underlying raw value to a Kelvin value, and the actual applied value should be the same. The difference comes from how the value is rounded or converted for display.Our team should look into which display approach is more appropriate.
Thank you very much for your feedback and for paying attention to the details.
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The actual reason is that Zigbee and Matter use mired as colour temperature unit instead of kelvin. What you see in the app is not the native unit.
2700 K in mired is 1.000.000 / 2700 = 370,37 which rounded to the nearest integer is 370 mired and that’s the warmest temperature accepted by the device.
Since 370 mired is the warmest possible, when converted back to kelvin is 1.000.000 / 370 = 2702,70 which rounded is 2703 K.
In other words, 2700 K and 2703 K is exactly the same in Zigbee and Matter lights, regardless of hardware or manufacturers. Apps may round it so the user is happy and doesn’t think they’re losing 3 K but it’s perfectly fine.
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