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Submission + - The anti-selfie: a slow, antique photographic process doesn't let you hide (medium.com)

eggboard writes: A tintype is a form of wet-plate collodion photography, which requires exposing a metal plate covered in fluid chemicals within a short period of time after applying the emulsion. The process is receptive only to blue light, which tends to emphasize wrinkles and capillaries. The results are both gorgeous and unforgiving, the opposite of the selfie that tries to blur, hide, or present the subject in the best light. It may be old fashioned, but more and more shops have sprung up to offer slow photography. One in San Francisco has produced piles of prints, but is shutting down as its owners pursue other endeavors.

Comment P-hacking. (Score 3, Insightful) 124

From TFA:

Perhaps the worst fallacy is the kind of self-deception for which psychologist Uri Simonsohn of the University of Pennsylvania and his colleagues have popularized the term P-hacking; it is also known as data-dredging, snooping, fishing, significance-chasing and double-dipping. "P-hacking," says Simonsohn, "is trying multiple things until you get the desired result" - even unconsciously.

Comment Re:Um... (Score 2) 239

Just change it to a extra-special-search list, and let people fly but check them carefully.

Probably not going to happen.

Politicians are, usually, very risk averse. They do not want to be THE ONE to push for a change that results in another terrorist taking over an airplane. Even if the likelihood of that is practically non-existent.

They don't care who's on the list or even if the list is valid as long as:
1. They (and their families/friends) are not on the list.
2. They are not directly responsible for being "weak" on anything.

Comment Re:Why the arms race ?? (Score 1) 376

Try also wearing something retroreflective if you're out on the bike at night. Anyone with full beams still on will get it reflected straight back at them (your retroreflectives will look as dazzling to them as they are to you). The plus point of retroreflectives is that the drivers of cars on dipped beams can see you well outside of the nominal range of the dipped headlights so they'll be able to recognise what you are a lot further away.

Comment Re:But why white light? (Score 1) 376

Streetlamps are orange or light orange not because of a design decision to use a wavelength at which we're sensitive, but merely because low pressure sodium lights are still by a country mile the most efficient high power lighting we have. Since LEDs are now beating high pressure sodium lights (the lighter yellow type), these are being increasingly replaced by LEDs.

We don't use sodium lights as car headlights because if you wanted to drive at night, you would have to get in your car and wait five or ten minutes for the lights to get up to temperature before you could drive anywhere. Watch one of the orange streetlights come on some time - they start a dull red (which always makes me crave strawberry ice lollies) - that's just the inert gas mix glowing - and it takes a while for the lamp to warm up enough for the sodium to vaporise before you start seeing the orange colour. High pressure Na lights start off a dim bluish white colour (mercury discharge) until the sodium has vaporised and they become full brightness.

Back when we started putting sodium streetlights up the only technology that could produce enough light for a car headlight and was also instant on was the incandescent bulb.

Comment Re:Blindness / Bad Idea (Score 1) 376

But is the incremental risk out of all proportion? You've not demonstrated this. First we know it's an LED laser. LED lasers tend not to put out a collimated beam - your laser pointer for instance isn't just a laser diode with a bit of protective glass on the front, it also includes a collimating lens to keep the beam narrow. Without this lens the beam of the naked laser diode would have about a 30 degree angle on it. The danger from powerful lasers is due to the beam being highly collimated (all the energy focused into one very small spot). If the beam without a lens spreads out at 30 degrees without a lens, it's not more dangerous than any other type of lamp of equivalent power with a beam spread out over an equivalent angle.

It's also highly likely that the laser, phosphor and lens will be one moulded assembly, so if you break the lens you're also pretty much likely to break the laser diode at the same time, and any significant disruption to the assembly will also ruin the heatsink causing the diode to overheat and fail quickly. It'll also not be trivial to disassemble, and will still require the addition of a collimating lens system to form a dangerous narrow beam.

Comment Re:Not blinded by laser but blinded nonetheless (Score 1) 376

It's also likely a product of when the law was made, and I wager this law was probably made when there were no conceivable technologies for car headlights other than incandescent bulbs (probably the legislation was written before LEDs were even invented, let alone the power illuminator LEDs that are available now). It was probably drafted by a civil servant then rubber stamped by parliament too.

Comment Re:It's a simple case of cost (Score 1) 473

The FAA does allow relatively inexpensive aircraft like the Auster Autocrat, indeed the FAA allows a lot more than what our country allows. Experimentals also shouldn't be discounted - many do NOT limit you and are far more capable than a certified aircraft five times as expensive. When I lived in the United States, I had a Cessna 140. This (about 10 years ago) worked out at about $19/hr, that's with everything included - hangarage, fuel, maintenance, insurance. It was in almost mint condition. (Part of the low hourly cost is that I flew it *a lot*, so the fixed costs were spread over a lot of hours - I owned it in a partnership with a friend and between us we flew her about 400 hours a year). Both my partner and his wife flew so although he was married, that wasn't a problem. When my contract in the US ended, I spent two months flying from coast to coast. It was awesome.

I can understand marriage putting an end to this. There is a phenomenon we have in GA called AIDS. It stands for Aviation Induced Divorce Syndrome.

Comment Re:I abandoned thoughts of getting a pilot's licen (Score 1) 473

1970s? Ours is 1940s technology in the cockpit! It's not the technology about flying that excites me. I don't really care about the technology. I fly to be in the air, not to play with technology.

If you only care about flying technology (you mentioned drones) I can really recommend getting into RC, it's something I do also (radio controlled helicopters, which is also a problem because they aren't cheap). RC helicopters (proper ones, single rotor ones) have a lot of interesting technology challenges because they are inherently unstable. There's quite a few various gyro and control boards from places like Sparkfun and if you really want to get your hands dirty there is a lot of interesting stuff you can do with a RC helicopter.

Comment Re:Blindness / Bad Idea (Score 1) 376

Some safeguards and cutoffs that failed safe and prevented disasters:

- Countless runaway trains have been prevented by failsafe brakes (vacuum in the early days, air brakes today).
- Countless boiler explosions prevented by safety valves
- Several nuclear explosions prevented by failsafe arming mechanisms when the bomber carrying the nukes crashed.

There's three. The thing is you only get to hear about the failures. A failsafe working and preventing a disaster is not news so no one ever reports it. But I can guarantee you every day dozens of industrial disasters are averted by failsafe devices like safety power cutoffs, pressure activated safety valves, braking systems that come on when there's an air leak, signalling systems that fail to "stop" when there's a system failure etc.

If we had your attitude we'd still be insisting a man with a red flag walk in front of every car.

Comment Re:Guarantee (Score 2) 716

Actually the builder offers a guarantee that the wall will be built to industry standards.

And to the exact specifications that were provided to him, in writing, at the time he bid for the job.

Try getting a builder to build the wall "just a bit higher" or "just a bit wider" or "just put a window in that patch you've finished already". Not going to happen.

Which is why programming is not the same as construction.

Indeed nobody would hire a builder who's contract stated that they offered no guarantee.

And, likewise, no builder would bit for a job that didn't have EVERYTHING already specified and signed off by a certified architect.

In software it is not possible in practice for someone to write a non-trivial program without any bugs.

The first problem in software is defining what a "bug" is. It's not a feature request. It's not something that was left out of the requirements.

If the employer can provide the same level of documentation for the program that a builder will be provided with then software "bugs" become a lot rarer.

Comment PPL reality check (Score 1) 473

Is current GA activity intrinsically low, or is it low compared to the Good Old Days of the 1950s and 1960s general aviation boom?

Our GA airports are somewhat less than inviting to visitors. There was an editorial/blog in Flying magazine on this subject recently.

Airplanes really are expensive to buy and to operate.

Does anybody learn to fly for fun or for private transportation anymore? Everybody nowadays gets their PPL because it's the prerequisite for everything else. After the novelty wore off I too came to the realization that a PPL was sterile, a dead end, and am now working on my commercial license.

...laura

Submission + - Contracept-apps (medium.com)

eggboard writes: There are a bunch of apps that help women (and their partners) manage fertility, to make it easier to conceive a child. But Natali Morris, the mother of two and planning no more, explains that they can be used for the opposite: contraception through careful measurement of vital statistics. For now, she'd rather avoid devices, hormones, and surgeries, and is using an app instead. It requires commitment and the scientific method, but it's not a quack idea; it conforms with modern knowledge of fertility cycles.

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