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[Iduno]

A while ago, I heard that Samsung were using the front camera as a substitute for the light sensor on phones that didn't have light sensors.
How do you determine the brightness of something using a camera?

Knowing Samsung? Poorly.

Non-joke answer? Measure the amount of light that hits the lens through a known aperture size in a given amount of time. Because there's no film being exposed, it's just a color sensors or whatever. (I know something about cameras, and very little about electronics outside of practical knowledge from using them).

[Reelya]

How do you determine the brightness of something using a camera?

Uhh. Kinda seems obvious. A camera is nothing but light sensors. Pixel information is literally nothing but brightness values. Take a picture and average out the levels of brightness of all the pixels and you have brightness sensor.

[methylatedspirit]

How do you determine the brightness of something using a camera?

Uhh. Kinda seems obvious. A camera is nothing but light sensors. Pixel information is literally nothing but brightness values. Take a picture and average out the levels of brightness of all the pixels and you have brightness sensor.

That works well enough to find relative brightness, assuming you keep the apeture, ISO and shutter speed constant. I don't have a clue how I'd do it if those parameters change, though.

Maybe I should rephrase my question: How do you determine absolute brightness, in units like candela/lux, with a camera?

[wierd]

Use a known candle to calibrate the sensor.  Use a light source that is not visible to human eyes, like IR.

Alternatively-- programmatically control the aperature, and shut it as tight as it will go. Open the aperature by fixed and controlled increments until there is enough exposure data to produce a luminance curve. Compute against aperature size and factory programmed ccd sensitivity metrics. That should give you a ballpark raw lux.

[Kagus]

My friend's a light eater, so for lunch he usually just eats lux and bagels.

[wierd]

Interesting.. how does he make the light spreadable? Theres a definite nobel prize in it for him.

[Kagus]

Interesting.. how does he make the light spreadable? Theres a definite nobel prize in it for him.

Light is both a wave and a condiment.

[scriver]

Try the new luxury butter

[methylatedspirit]

I tend to sleep in 1 to 2 hour intervals. I sleep at 10 pm, wake up at 12:30 am, sleep again only to wake up at 2 am, sleep yet again just to wake up at 3:30 and so on until 5 or 6 am. Is there some way to merge the sleeps together so I just sleep at 10, and wake up at 6 in the morning?

[hector13]

It’s normal to wake up a few times at night, though usually you don’t remember it.

There could be any number of reasons causing this, from stress to medication to the wrong temperature, or others.

Do you feel rested after sleeping?

[methylatedspirit]

Do you feel rested after sleeping?

No, not really. I track my sleep, and the data shows that I don't get much deep sleep, around 1 hour out of 6 to 8 hours of sleep.

[MaxTheFox]

Is a flamethrower a firearm?

[Frumple]

Apparently not. A firearm is something that expels a projectile by way of an explosion, more or less. Most flamethrowers don't do that. So not a firearm.

[Rolan7]

I'd count it as a "fire arm" though, like a "laser gun" or "sound cannon".  Or by that token, "bullet gun".
I forget what it's called to use a noun like an adjective that way.  It might even be improper, but there's precedent

[Frumple]

They're generally just an incendiary device. Not a gun of any sort. If you want a colloquial name, I hear "flamethrower" is in vogue