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I hear so much about f.lux, but to me I don't know if the science quite backs it up like everyone says it does. I've found it suffers from the, "They used the

I hear so much about f.lux, but to me I don't know if the science quite backs it up like everyone says it does. I've found it suffers from the, "They used the word science so it must be good" problem. Why hasn't anyone done a study on specifically what f.lux attempts to do? Sure, light at night causes people problems sleeping, but does f.lux actually make a difference? Can we quantify that difference in a way that controls for the fanboy (formerly known as placebo) effect?

polyfractal 13y ago
Result from a quick pubmed search (I haven't actually read the paper): http://www.ncbi.nlm.nih.gov/pubmed/24110034 http://www.ncbi.nlm.nih.gov/pubmed/24110034 >Effects of LED-backlit computer screen and emotional selfregulation on human melatonin production. >[...] Finally, we can also report that the blue light of LED-backlit computer screen significantly suppress melatonin production (91%) more than red light (78%) and no light (44%).
- diminoten 13y ago
  5 participants, eh? But hey, pubmed a.k.a. "science" says it, so it must be irrefutable.
  - polyfractal 13y ago
    sigh Fine, here are more articles. If you don't want to believe in peer-reviewed academic literature, I'm not sure why I'm bothering. Statistically significant results can be obtained with few participants. Behold the power of math. http://www.ncbi.nlm.nih.gov/pubmed/23926261 http://www.ncbi.nlm.nih.gov/pubmed/23926261 Nocturnal light exposure impairs affective responses in a wavelength-dependent manner. >Our results demonstrate that exposure to LAN influences behavior and neuronal plasticity and that this effect is likely mediated by ipRGCs. Modern sources of LAN that contain blue wavelengths may be particularly disruptive to the circadian system, potentially contributing to altered mood regulation. http://www.ncbi.nlm.nih.gov/pubmed/23358248 http://www.ncbi.nlm.nih.gov/pubmed/23358248 Out of the lab and into the bathroom: evening short-term exposure to conventional light suppresses melatonin and increases alertness perception. >Subjective alertness was significantly increased after exposure to three of the lighting conditions which included blue spectral components in their spectra. Evening exposure to conventional lamps in an everyday setting influences melatonin excretion and alertness perception within 30 min. http://www.ncbi.nlm.nih.gov/pubmed/21298068 http://www.ncbi.nlm.nih.gov/pubmed/21298068 Non-visual effects of light on melatonin, alertness and cognitive performance: can blue-enriched light keep us alert? Exposure to light at 6500K induced greater melatonin suppression, together with enhanced subjective alertness, well-being and visual comfort. With respect to cognitive performance, light at 6500K led to significantly faster reaction times in tasks associated with sustained attention (Psychomotor Vigilance and GO/NOGO Task), but not in tasks associated with executive function (Paced Visual Serial Addition Task). [...] Our findings suggest that the sensitivity of the human alerting and cognitive response to polychromatic light at levels as low as 40 lux, is blue-shifted relative to the three-cone visual photopic system. Thus, the selection of commercially available compact fluorescent lights with different colour temperatures significantly impacts on circadian physiology and cognitive performance at home and in the workplace.
    - MAGZine 13y ago
      good digging. upboats! i'm impressed with someone's ability to ask for someone else to do research, and then be snooty when someone finds it for them. I thought that the effects of blue light on circadian rhythms was clear-cut, popular knowledge.
      - diminoten 13y ago
        http://justgetflux.com/research.html http://justgetflux.com/research.html It's on their website. No one did any "research" except the people who made F.lux.
    - diminoten 13y ago
      This trickery may work on Reddit (I know you're from Reddit because you use carets to denote quotations), but allow me to repeat myself: Why hasn't anyone done a study on specifically what f.lux attempts to do? Sure, light at night causes people problems sleeping, but does f.lux actually make a difference? Can we quantify that difference in a way that controls for the fanboy (formerly known as placebo) effect?
      - DanBC 13y ago
        > (I know you're from Reddit because you use carets to denote quotations) What? People have been doing that for very many years. Here's TBL doing it in 1991 (https://groups.google.com/forum/#!msg/alt.hypertext/eCTkkOoWTAY/bJGhZyooXzkJ https://groups.google.com/forum/#!msg/alt.hypertext/eCTkkOoW...)
        diminoten 13y ago
        We don't disagree.
      - polyfractal 13y ago
        Haha, what? That is the most bizarre insult? argument? that I've seen in a while. People use greater-than characters all the time for quotations. It's been used in email forever. But bonus points for trying to be edgy I guess. To your question: All the studies are basically examining the principle that f.lux operates on. Shift colors away from blue and you can limit the decrease in melatonin production. I don't understand your question? If you mean, "why has no one done a study on f.lux itself?", then I'm assuming no one has done a study on f.lux per se because (I'm just guessing here) no serious academic researcher really gives two shits about a piece of software on the internet. However, that doesn't mean their research cannot be applied. F.lux is applied science, working on a fairly solid base of academic research. Real science with, yunno, quantifiable and statistically significant results. It isn't "fanboyism" or "science"...it is peer-reviewed literature. The articles I linked specifically talk about how spectral blue light decreases melatonin production (a hormone directly related to how sleepy you feel at night) and a corresponding increase in alertness. Doing a little extrapolation, if you decrease the amount of blue light that you are exposed to in the evening you decrease the impact on melatonin production and increased alertness. So sure, I doubt anyone has stuck a person in front of f.lux and measured salivatory melatonin levels...but they have done the equivalent with blue and red lights. It isn't reaching to say that f.lux is doing exactly the same thing.
  - aggie 13y ago
    I don't see anyone saying it's irrefutable. It's a conference proceeding, which means it's essentially a progress report on a line of research. And small sample sizes can produce compelling evidence if there is a large effect size observed, particularly with the objective physiological measures (subjective psychometrics are much more susceptible to bias). This research is also likely to be supported by other studies, making this essentially replication of an observed effect.
  - lectrick 13y ago
    In case you were sleeping during Stats 101: http://en.wikipedia.org/wiki/P-value http://en.wikipedia.org/wiki/P-value
joverholt 13y ago
Look up how blue led light can disrupt sleeping. Ever notice how bright blue led is compared to others (red, yellow)? My cable modem has blue leds for the indicator lights, and in a dark room, it is amazing how bright they are. f.lux makes your monitor use less of the blue components of light and more of the reds. It will make your screen look funny till you get used to it, which takes minutes. To really see what it does, in a darkened room, turn off f.lux
- diminoten 13y ago
  The connection between light colors and what f.lux does is the connection I have a hard time making.
  - jlgreco 13y ago
    f.lux adjust light colors. What about the connection between light colors and what f.lux does is confusing you?
    - diminoten 13y ago
      The part where F.lux removes brightness magically, then. Bring your laptop under your covers one night. Load up a completely black page. Can you still see (hint: probably)? There is between almost none and a whole lot of white light that leaks out of monitors, regardless of what each pixel is set to let through. Does that matter? None of these linked studies have examined that, to my knowledge.
      - shubb 13y ago
        The LCD in your monitor is a filter, that controls what colors from the white back-light reach your eyes. It is not completely effective - when the LCD is set to block all colors, there is some white-ish leakage as you say. A completely red shape on an LCD would still have some blue in it from the leakage. We perceive color and brightness relative to the other colors close by. Flux shifts the color balance of the screen towards red at night. After your eyes get used to it, the colors look about right, but the LCD is in fact blocking a higher proportion of blue than normal. What it does not do is change the brightness of the screen - this is usually done by changing the intensity of the backlight. It is bad for you to look at a screen that is either too bright or too dark for the room you are in, so this is best done with an actual light sensor. Here is a thread about doing that, but neither of the programs in it work very well. If you fancy making an open source program to do this, you'll be my hero :-) http://superuser.com/questions/284706/webcam-as-ambient-light-sensor-in-windows-7 http://superuser.com/questions/284706/webcam-as-ambient-ligh...
jlgreco 13y ago
The difference I use Redshift for is how much my eyes hurt at night the second I turn it off and everything shifts bluer. Whether or not it changes my sleeping patterns, I cannot say, but it is more pleasant at least.

polyfractal 13y ago

Result from a quick pubmed search (I haven't actually read the paper): http://www.ncbi.nlm.nih.gov/pubmed/24110034 http://www.ncbi.nlm.nih.gov/pubmed/24110034 >Effects of LED-backlit computer screen and emotional selfregulation on human melatonin production. >[...] Finally, we can also report that the blue light of LED-backlit computer screen significantly suppress melatonin production (91%) more than red light (78%) and no light (44%).

diminoten 13y ago
5 participants, eh? But hey, pubmed a.k.a. "science" says it, so it must be irrefutable.
- polyfractal 13y ago
  sigh Fine, here are more articles. If you don't want to believe in peer-reviewed academic literature, I'm not sure why I'm bothering. Statistically significant results can be obtained with few participants. Behold the power of math. http://www.ncbi.nlm.nih.gov/pubmed/23926261 http://www.ncbi.nlm.nih.gov/pubmed/23926261 Nocturnal light exposure impairs affective responses in a wavelength-dependent manner. >Our results demonstrate that exposure to LAN influences behavior and neuronal plasticity and that this effect is likely mediated by ipRGCs. Modern sources of LAN that contain blue wavelengths may be particularly disruptive to the circadian system, potentially contributing to altered mood regulation. http://www.ncbi.nlm.nih.gov/pubmed/23358248 http://www.ncbi.nlm.nih.gov/pubmed/23358248 Out of the lab and into the bathroom: evening short-term exposure to conventional light suppresses melatonin and increases alertness perception. >Subjective alertness was significantly increased after exposure to three of the lighting conditions which included blue spectral components in their spectra. Evening exposure to conventional lamps in an everyday setting influences melatonin excretion and alertness perception within 30 min. http://www.ncbi.nlm.nih.gov/pubmed/21298068 http://www.ncbi.nlm.nih.gov/pubmed/21298068 Non-visual effects of light on melatonin, alertness and cognitive performance: can blue-enriched light keep us alert? Exposure to light at 6500K induced greater melatonin suppression, together with enhanced subjective alertness, well-being and visual comfort. With respect to cognitive performance, light at 6500K led to significantly faster reaction times in tasks associated with sustained attention (Psychomotor Vigilance and GO/NOGO Task), but not in tasks associated with executive function (Paced Visual Serial Addition Task). [...] Our findings suggest that the sensitivity of the human alerting and cognitive response to polychromatic light at levels as low as 40 lux, is blue-shifted relative to the three-cone visual photopic system. Thus, the selection of commercially available compact fluorescent lights with different colour temperatures significantly impacts on circadian physiology and cognitive performance at home and in the workplace.
  - MAGZine 13y ago
    good digging. upboats! i'm impressed with someone's ability to ask for someone else to do research, and then be snooty when someone finds it for them. I thought that the effects of blue light on circadian rhythms was clear-cut, popular knowledge.
    - diminoten 13y ago
      http://justgetflux.com/research.html http://justgetflux.com/research.html It's on their website. No one did any "research" except the people who made F.lux.
  - diminoten 13y ago
    This trickery may work on Reddit (I know you're from Reddit because you use carets to denote quotations), but allow me to repeat myself: Why hasn't anyone done a study on specifically what f.lux attempts to do? Sure, light at night causes people problems sleeping, but does f.lux actually make a difference? Can we quantify that difference in a way that controls for the fanboy (formerly known as placebo) effect?
    - DanBC 13y ago
      > (I know you're from Reddit because you use carets to denote quotations) What? People have been doing that for very many years. Here's TBL doing it in 1991 (https://groups.google.com/forum/#!msg/alt.hypertext/eCTkkOoWTAY/bJGhZyooXzkJ https://groups.google.com/forum/#!msg/alt.hypertext/eCTkkOoW...)
      - diminoten 13y ago
        We don't disagree.
    - polyfractal 13y ago
      Haha, what? That is the most bizarre insult? argument? that I've seen in a while. People use greater-than characters all the time for quotations. It's been used in email forever. But bonus points for trying to be edgy I guess. To your question: All the studies are basically examining the principle that f.lux operates on. Shift colors away from blue and you can limit the decrease in melatonin production. I don't understand your question? If you mean, "why has no one done a study on f.lux itself?", then I'm assuming no one has done a study on f.lux per se because (I'm just guessing here) no serious academic researcher really gives two shits about a piece of software on the internet. However, that doesn't mean their research cannot be applied. F.lux is applied science, working on a fairly solid base of academic research. Real science with, yunno, quantifiable and statistically significant results. It isn't "fanboyism" or "science"...it is peer-reviewed literature. The articles I linked specifically talk about how spectral blue light decreases melatonin production (a hormone directly related to how sleepy you feel at night) and a corresponding increase in alertness. Doing a little extrapolation, if you decrease the amount of blue light that you are exposed to in the evening you decrease the impact on melatonin production and increased alertness. So sure, I doubt anyone has stuck a person in front of f.lux and measured salivatory melatonin levels...but they have done the equivalent with blue and red lights. It isn't reaching to say that f.lux is doing exactly the same thing.
- aggie 13y ago
  I don't see anyone saying it's irrefutable. It's a conference proceeding, which means it's essentially a progress report on a line of research. And small sample sizes can produce compelling evidence if there is a large effect size observed, particularly with the objective physiological measures (subjective psychometrics are much more susceptible to bias). This research is also likely to be supported by other studies, making this essentially replication of an observed effect.
- lectrick 13y ago
  In case you were sleeping during Stats 101: http://en.wikipedia.org/wiki/P-value http://en.wikipedia.org/wiki/P-value

joverholt 13y ago

Look up how blue led light can disrupt sleeping. Ever notice how bright blue led is compared to others (red, yellow)? My cable modem has blue leds for the indicator lights, and in a dark room, it is amazing how bright they are. f.lux makes your monitor use less of the blue components of light and more of the reds. It will make your screen look funny till you get used to it, which takes minutes. To really see what it does, in a darkened room, turn off f.lux

diminoten 13y ago
The connection between light colors and what f.lux does is the connection I have a hard time making.
- jlgreco 13y ago
  f.lux adjust light colors. What about the connection between light colors and what f.lux does is confusing you?
  - diminoten 13y ago
    The part where F.lux removes brightness magically, then. Bring your laptop under your covers one night. Load up a completely black page. Can you still see (hint: probably)? There is between almost none and a whole lot of white light that leaks out of monitors, regardless of what each pixel is set to let through. Does that matter? None of these linked studies have examined that, to my knowledge.
    - shubb 13y ago
      The LCD in your monitor is a filter, that controls what colors from the white back-light reach your eyes. It is not completely effective - when the LCD is set to block all colors, there is some white-ish leakage as you say. A completely red shape on an LCD would still have some blue in it from the leakage. We perceive color and brightness relative to the other colors close by. Flux shifts the color balance of the screen towards red at night. After your eyes get used to it, the colors look about right, but the LCD is in fact blocking a higher proportion of blue than normal. What it does not do is change the brightness of the screen - this is usually done by changing the intensity of the backlight. It is bad for you to look at a screen that is either too bright or too dark for the room you are in, so this is best done with an actual light sensor. Here is a thread about doing that, but neither of the programs in it work very well. If you fancy making an open source program to do this, you'll be my hero :-) http://superuser.com/questions/284706/webcam-as-ambient-light-sensor-in-windows-7 http://superuser.com/questions/284706/webcam-as-ambient-ligh...

jlgreco 13y ago

The difference I use Redshift for is how much my eyes hurt at night the second I turn it off and everything shifts bluer. Whether or not it changes my sleeping patterns, I cannot say, but it is more pleasant at least.