F.lux showing wrong color temp on calibrated display?



  • Hi everyone -

    F.lux is great! Thank you for offering and supporting it!

    I have a ThinkPad X1 Carbon running Win 7 x64, and I've calibrated my display to a 4000K white point using an i1 Display device.

    When I turn on f.lux and set its color temp to ~ 4000K using the presets, my display gets much warmer than without f.lux. So it appears that on my system the color temp values in f.lux are very incorrect!

    Is this happening because f.lux expects that a calibrated display has a 6500K white point? And f.lux is not aware of the white point of my current display profile?

    If I would like to continue using my 4000K profile with f.lux, can you tell me how to roughly compute the color temp that f.lux is producing? For example, can I infer that with my setup, when f.lux says I'm at 4000K that I'm really 1500K (i.e. 2500K less than expected)?

    I like using the 4000K display profile because it blocks the blue light while maintaining color accuracy. But 4000K is the lowest white point that the i1 software will target, so f.lux is still useful to me!

    Thank you in advance for the assistance.

    Brian



  • @kablamo Calibrate your screen to 6500K and set f.lux to 4000. Then you can set it to normal when you'd like more daylight color.



  • @Tungsten_smooth So, just to be clear, f.lux does expect your display to be at 6500K? And it does not know if you have a different white point?

    If I would like to leave my calibration at 4000K, for the reasons I described, how can I (roughly or precisely) calculate the white point that f.lux is producing?

    Thanks,
    Brian



  • @kablamo said:

    @Tungsten_smooth So, just to be clear, f.lux does expect your display to be at 6500K? And it does not know if you have a different white point?

    If I would like to leave my calibration at 4000K, for the reasons I described, how can I (roughly or precisely) calculate the white point that f.lux is producing?

    Thanks,
    Brian

    We don't know the inner workings of f.lux like that. The only people who could really tell you would be Michael and Lorna. They are the f.lux team. My friend Tungsten_smooth and I are just fans of f.lux.

    I would like to point something out though, and I think you already figured this out but you're just not sure if you're right (and I think you are): you have your display calibrated to 4000K. So, I would expect f.lux's 6500K to start at 4000K because it's apparently being limited to what you've calibrated your monitor to. Y'know? I mean, it seems that you discovered that f.lux would have to completely override your calibration in order for you to actually see 6500K when f.lux is set to 6500K.

    To be honest, I don't think it matters what the numbers say. As long as you are getting the look that you want, that's all that matters. It's kind of like adjusting your volume, or adjusting the temperature in your home: the number you set it to is almost meaningless. Go by how it sounds, or by how it feels.

    Having said that though, I think you're right that since you have it calibrated to 4000K, you can probably assume that any setting you have f.lux set to should have 2500 subtracted from it to get a rough estimate of the actual color temperature you're looking at.



  • Thank you for the thoughts. I am indeed currently using f.lux like a volume knob to boost the blue-blocking!

    It does appear that f.lux is not aware of, and does not compensate for, my calibration profile targeting 4000K.

    Recognizing that fixing this problem may not be a near-term priority for the developers, I was just wondering if it really is just a linear offset across the temp range, or something else, or if there is any other guidance on using f.lux with a calibration profile.

    The FAQ mentions calibration but not this particular issue.

    Thanks again,
    Brian



  • @kablamo said:

    Thank you for the thoughts. I am indeed currently using f.lux like a volume knob to boost the blue-blocking!

    It does appear that f.lux is not aware of, and does not compensate for, my calibration profile targeting 4000K.

    Recognizing that fixing this problem may not be a near-term priority for the developers, I was just wondering if it really is just a linear offset across the temp range, or something else, or if there is any other guidance on using f.lux with a calibration profile.

    The FAQ mentions calibration but not this particular issue.

    Thanks again,
    Brian

    I would say, just go by how it looks. You don't really have to know your color temperature.


Log in to reply
 

Looks like your connection to f.lux forum was lost, please wait while we try to reconnect.