Making a quick post about Redshift

So redshift is a cool program that, contrary to the name, actually makes your screen more yellowish orange, instead of a pink or red tone as you may think. It’s designed to help you wind down at night and there are lots of research pages about it. I’ve already linked to a few pages in another forum section, but I really would like to raise awareness, so I hope it’s O.K. if I post here to.

I’ll add to this shortly, but I wanted to get a discussion going hopefully!

**TL;DR *Your computer monitor is very bright and delays your sleep at night. The light it gives off attempts to match daylight. *We are now constantly seeing light, well after sundown. This delays our sleep because our bodies think it’s not night time anymore, and get very confused for a couple hours or so.

This can also help cause a variety of diseases (notice i said help cause) such as: diabetes, breast cancer, depression, high blood pressure, and even cancer. I could get into specifics but this is a TL;DR, and now I have to expand on the original post to explain what I put here about the diseases part. damit!

  • Reduce the brightness of the screen with the on screen buttons.
  • I
    nvert the screen colors, also do this with phones and tablets! - Redshift
    takes away the bright alerting colors at night, in exchange for a more relaxing output of the screen, like reading a book by candle light.

You’re computer screen is usually 24 inches or closer to your face, and most now are 22" or larger. The bigger something is, the more light it emits. What I mean is, if you have a larger monitor, it’s going to emit more light, even if it’s the same “cd/m2” or brightness level as your phone, or anything. If two things are the same brightness, the larger one is emitting more light, because it’s a larger space.

Most people also don’t adjust their brightness, and that’s got a be bright at night, but I guess it doesn’t bother some. I find it very odd and also uncomfortable to look at *any *bright screens at night, and if there is a regular LED (not oled because PWM) cellphone screen on maximum brightness at night, I just ask people to dim it back down. I hope autobrightness on phones improve.

Anyway, our sleep and wake times are largely controlled by the light we see. We’ve only had bright lights for the past ~50-60 years or so. I’m not an “expert” on the history of light bulbs, but I think the bright metal halide stuff and fluorescent lights came around in the 50’s or so? Google has the answer for all that. My point is, just half a century ago, our world was not blanketed in light all the time.

Light is great, but it’s getting out of hand with light pollution, and disregard or not knowing the effects it has on sleep and wakefulness. We don’t teach it in schools, and I really think we should–it’s something we see every day of our life. It’s a big deal.

I have a couple plug in lamp dimmers that I use all the time in the evening, and they are very cheap ~$10 or so. They plug into the wall, then you plug in your lamp or whatever into the outlet for the device, very simple. When you dim down an Incandescent bulb, it gets more yellow / orange in appearance.

When the sun sets, it gets more orange in appearance. It’s extremely similar. When the sun sets, and everything goes back to the bluish daytime color, things start to get much darker, to the point where we can barely see after about an hour and a half. That’s obviously why we use artificial light.

So why yellow? or orangish yellow? We are wired to relax when we see the sun setting, then everything starts getting dark, fast. When there is less light available, we get sleepy. There is a hormone called “Melatonin” that gets produced–but more so in darkness. When you have a bright light on, that sends the signal to your brain that it’s not night time, but now the sun is somehow up again–it’s not immediate, but it will affect when you go to sleep, and also how sleepy you feel.

Monitors emit 6,500K (K is for Kelvin, not 1,000. I’ve seen many people be confused by that). Kelvin is a measurement of color.

Here is Kelvin chart (I try to find ones that are actually accurate):
Yes, moon light truly is 4100K or very very close to it

The higher the number, the more white, or after around 7,000K more bluish. Warm white, yellowish tones, like 2700K and especially 1,900K is very relaxing. 1,900K is where a candle usually is, and this very very low amount of light is what we used in homes after dark. I’m sure that was tedious, but it really did keep our sleep in check. There’s no doubt about that.

Redshift will tone down your screen, and in a way I think is accurate, and will provide only warmer tones of blues and greens. It cuts down on bright blue, and at low enough settings, can become a dark green even. It really help keep away the alerting colors of the computer screen, so you can relax and wind down for the night.

I’d also recommend you invert your colors, white backgrounds become a dark color (not really black, but close, because backlights) This will make your screen IMMENSELY darker, and it’s something I think everyone should do, regardless of what you do with the color of any screen–most phones will also let you invert the screen colors, do it there too.

More of an edit here, as I put some stuff in the TL;DR as this is getting extremely long, and I discussed how this can help cause diseases, and I’d like to highlight a few things.

For diabetes: When you don’t sleep well at night, you are more inclined to wake up and crave sweet foods to increase your energy levels. So yes, looking at a bright white monitor at night can degrade both your sleep, and your eating habits.

For breast cancer: I don’t have specifics on this, but there are links pertaining to women working the night shift, and getting breast cancer… sorry I wish I had more for that.

For depression: There are reports that after having a child, women can get depressed (I’m not a woman, and I don’t really understand why this would happen but anyway). This depression can be exacerbated by exposure to bright lights at night. The lack of sleep can put you in a worse mood, and eventually you can become depressed because of it. Crazy eh?

That’s all I’ve got, and if you’d like links to where I’m pulling this information, I could try to find all of it, but for now, it all comes from my brain.

If you’d like to discuss anything in this post, please don’t hesitate to add a post to this thread!

On Wed, 20 Apr 2016 01:26:01 +0000, timpster wrote:

> If you’d like to discuss anything in this post, please don’t hesitate to
> add a post to this thread!

We’re glad that you’re a fan of redshift, really - but this is the third
thread you’ve started in three years about this - two of which were
within the past few days.

As I’ve said, I use it, and it helps me. But I do think that it’s a
little overboard to make medical claims here, as this is not a medical
forum. If people want to learn more, I would recommend they seek advice
from a medical professional.

Thanks. :slight_smile:


Jim Henderson
openSUSE Forums Administrator
Forum Use Terms & Conditions at

So too much? O.K., I was told it was a good idea to revive older threads, but I get the idea. Whoops!

On Wed, 20 Apr 2016 18:56:01 +0000, timpster wrote:

> So too much? O.K., I was told it was a good idea to revive older
> threads, but I get the idea. Whoops!

Not a huge problem, it’s just that since I’m not a medical professional
(and I don’t recall that anyone on staff is), and it’s not clear whether
you are or not, we should probably leave medical claims to those who work
in that field - we wouldn’t want readers here to mistakenly think that
any post here contained medical advice.

I’m glad you understand. :slight_smile:


Jim Henderson
openSUSE Forums Administrator
Forum Use Terms & Conditions at

Fantastic post, save for the already mentioned medical claims. If you could post a scientific journal, it would be nice, otherwise it just might scare a bunch of people.

But all in all, quality post, thank you, after a couple of years I’ll start using redshift again.