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And so people learn to not make noise. And another broken system remains entrenched, forever.

Tetrachromats from my understanding don't see more of the spectrum, they just have better discrimination of the colors within it.

There's something that tends to go unrecognized, a function of the way our monitors work. Any color that is made of multiple primaries, such as magenta, cyan, or yellow, will naturally be brighter because more photons are emitted from the display. Not twice as bright, since our eye response is non-linear, but noticeably brighter.

Yup. This is precisely why the first image seems to have oscillating brightness, with clear sharp peaks at yellow and cyan. It's because it's not just changing color, it's literally twice as much light. It goes:

  Red - 1x
  Yellow - 2x
  Green - 1x
  Cyan - 2x
  Blue - 1x
  Magenta - 2x
(Of course magenta is not part of the spectrum.)

A very first step towards a better spectrum is just to maintain constant output brightness (accounting for gamma). There will still be perceptual differences in brightness, as we naturally perceive green as brighter than blue.

Obviously this gets taken into account by the time the author gets to the CIE color model. But there are a number of "intermediate" improvements like that, which you can make.


Most monitor reviews I've seen measure levels for black, white AND grey.

In the US they've even banned selling new old stock. I believe that was a recent change within the last few years.


Back in the 1970's I tried to come up with a metric time system by breaking a day into powers of 10. A centiDay was 14.4 minutes.

I realized it would never catch on, because a 30 minute TV show would have to fit into 28.8 minutes, and the only way to do that was to lose a couple of commercials. Never gonna happen.


Back in the 1790s some Frenchmen did the similar thing but, despite not having TV and commercials it still did not catch up even in France.


Grace Hopper used to hand out pieces of wire to represent nanoseconds. She used pepper to represent picoseconds.


I was able to do something similar by using gross approximations and conversions to/from metric. My coworker had just bought a surplus stainless steel water tank for solar heating, and was wondering how much it would weigh when full. It was cylindrical, so I asked him for the diameter and the height. In my head I converted those measurements to inches, then to centimeters by multiplying by 2.5. I divided the diameter by 2, squared it, and multiplied by 3 (close enough to pi) to get the area. Then I converted the area and the height to their nearest power of 2 so I could take advantage of logarithms. Multiplying the area and height was as easy as adding the exponents, which gave me cubic centimeters. The weight of water is almost by definition 1 gram per 1 cc. Divide by 1000 to get kg by subtracting 10 from the exponent, then multiply by 2 to get approximate pounds by adding 1 to the exponent. By the time he was done telling me the dimensions, I had an answer for him. It definitely wasn't correct, but all he needed was a ballpark anyway.


I love the way 360 (degrees) divides evenly by so many small integers: 2, 3, 4, 5, 6, 8, 9, 10, 12, 15.


I created 360 shares in a small business I set up many years ago incase we ever needed to a few more share holders


We may get there eventually just as a consequence of being part of the world economy.

I noticed a couple of years back that my "U.S. Customary" wrenches weren't fitting my new plumbing fittings which were definitely not metric, but metric wrenches did. Probably made in China.

Then last summer I noticed something similar with lag bolts. The U.S. Customary socket fit the head, but it was nearly identical to a metric one that fit just a little better. The threads are designed to go into wood, not a nut, so if they were metric you'd never even know.


But not same-day. But even that's a bit iffy - I made a purchase from Amazon recently where they promised same-day delivery, on a Sunday no less! But it didn't actually arrive until Wednesday.


You’re saying that you still use Amazon because it offers a superior delivery service?

Then aren’t you glad that option exists when you need it?


I didn't need it that same day - if I had, I would have driven 5 miles to the nearest retailer that carried it and Amazon wouldn't have even been considered.

I was seriously impressed that they made that promise, thought I had nothing to lose. And I re-learned a lesson, if something's too good to be true then it probably isn't. I certainly won't be putting any faith in same-day service in the future. They proved their "superior delivery service" is just an illusion.


But it sounds like their superior delivery service is a lie too. Promise next day or 2 day service but delivery in 3-4 days.


It wasn't even next day, it was same day! But yes, it was a complete lie.


Despite that, this user is telling us that’s why they don’t want to order on a another site.


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