Please create an account to participate in the Slashdot moderation system


Forgot your password?

Slashdot videos: Now with more Slashdot!

  • View

  • Discuss

  • Share

We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).


Comment: Re:White balance and contrast in camera. (Score 1) 217

by drinkypoo (#49154329) Attached to: Is That Dress White and Gold Or Blue and Black?

(gold is FFD700, defined by HTML standards).


Pardon my caps, but I set a lot of these, and they are rarely stepped in so beautifully. That's my fault, of course. But, here we go.

When you hear the name of a color, you think of some color which you associate with that, or a thing which you think of as being that color which actually has a whole texture, reflectivity, depth, etc. But the truth is that the same name is being used right now by a dozen different paint companies to describe a dozen different colors, which are then described in thousands of different ways by the downstream users of the paint. There are some absolute color standards based on elements, oxides of the same and the like, but even those are frequently "abused". The truth, though, is that outside of a small handful of colors, they are not defined by any unifying principle. Your use of the HTML standards is particularly hilariously perfect, I really hope that you meant to put your foot there! Outside of web design, nobody but nobody gives a crap about that. Before that, we had the X rgb.txt file, which nobody outside of X-land cared about, which begat HTML colors by the way, junior. But meanwhile, over in the land of professional color, there were multiple competing color standards including AGFA and Pantone — and there still are.

It's interesting that part of this debate is also over the color "black" because "black" is what you see when you don't see anything, and if any part of the dress were truly black then the photograph would look like an editing mistake. Even the color black is subjective. That should be intuitively obvious to a web designer (who else would even mention HTML colors?) who has to deal with the real-world effects of differing black and white levels all day. I may be sitting at a monitor with 120% color (Adobe gamma) but I don't expect other people to have them. As far as I know, there is no color correction e.g. for Android which is not manual, and then the color adjustments become utterly perceptual.

I suspect that celebs are adept at perceiving the actual color of the dress because they have appeared in so many washed-out photographs.

Comment: Re:Hmmm (Score 1) 65

by Rei (#49153883) Attached to: Hyperloop Testing Starts Next Year

Technically, yes, with the caveat that you'd need regular floating reboost platforms with significant power generation scattered all throughout the Pacific, and of course maintaining the track perfectly straight while floating (one presumes at a fixed depth under the water) provides its own engineering challenges. But room-temperature rarified hydrogen instead of rarified air would allow one to make the journey at about Mach 4. Faster if it's hot hydrogen.

Comment: Re:This isn't new (Score 1) 65

by Rei (#49153867) Attached to: Hyperloop Testing Starts Next Year

Are you under the misconception that hyperloop is a pneumatic tube system?

Hyperloop is a magnetically-accelerated a ground-effect aircraft operating in the sort of extremely rarified air normally only found at high altitudes. The tube's purpose is to provide such a rarified atmosphere near the ground. It's not a pneumatic train. It's not a vactrain. It's not maglev. It's a ground-effect aircraft.

Comment: Re:It's almost like the Concord verses the 747 aga (Score 1) 65

by Rei (#49153847) Attached to: Hyperloop Testing Starts Next Year

Branching would be really tricky, but there's no physical barriers. Note that even Musk's proposal isn't as far as you can take the concept. If you fill the tube with very low pressure water vapor instead of very low pressure air (via more pumping to overwhelm leaks, plus water vapor injection), your top speed jumps 40%. Fill it with hydrogen and it jumps 300% (normally hydrogen is a real pain to work with due to flammability, embrittlement, etc, but the densities in question are so low that such issues are mostly avoided). So we're talking the potential for hyperloop "speedways" for long distance runs that could blow airplanes out of the water.

The low numbers of passengers per capsule is really key to making the concept economical. Compare, say, monorail track with a full sized rail bridge. The former is vastly cheaper per unit distance because the peak loadings are so much lower, because the mass of the monorail trains are so much lower. A computer-controlled high launch rate of small, high speed capsules means you're spreading the loading out greatly, which means greatly reduced loading and thus materials costs.

Still, while Musk has been thinking of Hyperloop stations in the "airport" concept, he really needs to get out of that mindset. His proposed plan had them on the outskirts of cities. Airports are only on the outskirts of cities because they *must* be. You greatly reduce your utility by doing that, by making people catch connecting trains. Hyperloop can extend just fine into towns; with his two proposed endpoints in particular there are excellent rail routes into town that are quite straight that it could be built over.

Comment: Re:It's funny (Score 1) 187

by Opportunist (#49153839) Attached to: We Stopped At Two Nuclear Bombs; We Can Stop At Two Degrees.

And this is where the whole deal breaks down, because there will never be such a thing. Nobody will be forced.

The only ones that could enforce something like this are the politicians, leaders of states that can create laws. Such laws will not come into existence, though, since that would require a global consensus because one country doing such a move alone will invariably cripple its economy. Global treaties that are supposed to be more than a stack of paper with letters, i.e. treaties that will be enforced and heeded on the other hand require the backing of industries that have an interest in such treaties coming into existence.

And industries have no interest in such a treaty. Quite the opposite. So if anything, we'll see a lot of resistance for such an international treaty taking place. Hence ... well, it's nice that we might know the world is fucked, but nobody who could give a shit gives a half of one.

Comment: Re:It's funny (Score 1) 187

by Opportunist (#49153801) Attached to: We Stopped At Two Nuclear Bombs; We Can Stop At Two Degrees.

I'm generally detached about things I'm powerless to influence. I'm usually the only calm person in a plane flying through a hurricane. Is there anything I can do? No. Why bother getting worked up about it?

Believe me, if I had to fly that plane, I'd be nervous as hell, but in the passenger seat... lean back and enjoy the roller coaster ride.

Comment: Re:White balance and contrast in camera. (Score 1) 217

by drinkypoo (#49153513) Attached to: Is That Dress White and Gold Or Blue and Black?

pretty much every pixel in the "blue" area has a B value about 20%-30% higher than the R or G value. That, to me, makes it about as objectively blue as it's possible to be.

Are you kidding? It's possible to be balanced far more towards blue. But also, gold is not a color. I learned back in my Amiga-using, pixel-editing days that there's a lot of blue in most metallics. I don't know if that's an artifact of what happens to light when it bounces off of them, or what, sorry. Not a physicist. But I know that if you're trying to make something look metallic, you're going to be adding some blue to it.

Comment: Idiotic comparison (Score 1) 187

by drinkypoo (#49153283) Attached to: We Stopped At Two Nuclear Bombs; We Can Stop At Two Degrees.

Not only (as others have pointed out) did we not stop at two, but setting off nuclear bombs is just a thing you can decide not to do. We may well be past the point of climate runaway, and if that's so then we would have to engage in concerted effort to prevent the imminent demise of the relative condition of biostasis we've enjoyed all the time.

Or hell, maybe the next ice age cycle will solve the problem, through some as-yet-unimagined mechanism. The question then becomes whether we'll survive that.

Comment: Re:White balance and contrast in camera. (Score 3, Informative) 217

by drinkypoo (#49153269) Attached to: Is That Dress White and Gold Or Blue and Black?

The thing is, in the provided picture, the dress actually IS white and gold, or at least grey and gold. Load it up in an editor and snip pieces of it out if you don't believe me, look at them on their own, compare them to color swatches. That doesn't make the dress any particular color. It makes the picture a particular color. The "white"/"black" part is banging right around 50%, which is clearly neither white nor black.

The camera diddled the image, maybe it was diddled even more before we actually saw it. Then we're all amazed that it doesn't look like the thing. But people have accidentally been taking pictures of things which don't look like things since time immemorial. They're called shitty pictures.

"An entire fraternity of strapping Wall-Street-bound youth. Hell - this is going to be a blood bath!" -- Post Bros. Comics