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Comment: Re:Working as designed (Score 1) 224

by popoutman (#49344779) Attached to: $1B TSA Behavioral Screening Program Slammed As "Junk Science"
Considering how the US gets laws passed, that's a definition of corruption where I live. It's corruption for a representative to take bribes in return for voting particular ways. The fact that it's done openly and has no outcry from the public always amazes me and tells me that the voting public are complicit in this. It's also considered corruption not to have the civil service draft the actual law text - where in the US the representative brings the text to the floor.

Another way that the US system is thoroughly broken, is the way that bills in most other countries are exactly for the purpose of the bill where in the US you have the riders and amendments that have absolutely nothing to so with the main bill.

When the free market extends into politics, it can only mean bad things for those that cannot afford to purchase their public representatives the same way that the corporates can..

Comment: All the bikes! (Score 1) 304

by popoutman (#49151815) Attached to: I ride a bike ...
I currently own 4 bicycles so I've no real excuse not to go riding...

One is a commuter bike piece of crap singlespeed (at least it's got 105 brakes that work) that I can leave locked up in the university overnight without much worry about theft. The next bike is my full-carbon Trek Madone 4.5 road bike, with nice upgraded Mavic Ksyrium wheels with the blade spokes. After that is a Giant Reign X1 "cross-country" mountain bike with 6.7" suspension in the rear, with some lightening done to the bike. Last but not least is my carbon Santa Cruz V10 full-on absolute top of the range 10" suspension downhill bike - which is actually lighter than my XC bike.

I try to ride at least once a week for a few hours on either the Trek or the Giant, reserving the V10 for uplift days at the local bike park or the annual trip to the Alps to take advantage of lift-serviced trails. The commuter bike is great for cycling in to meet my mates for lunch or for drinks in the evening as I won't drink and drive.

Biking is great. I get to see some lovely parts of the country, and the views at the top of the climbs are nearly worth it, but the descending really does make it all worthwhile!

Though I do need a secure shed instead of having the bikes in my kitchen..

Comment: Re:Not that easy to see (Score 1) 53

by popoutman (#48890781) Attached to: Rare Astronomical Event Will See Triple Moon Shadows On Jupiter
I'll bite.. It's worth noting that your rebuttal statement is not consistent, plus it sets up a little strawman that I will now proceed to take down.

You can have either a doubling of aperture and have the power the same, or you can have double the aperture and double the power and have the f/ratio the same.

If you have a doubling of aperture and maintaining the magnification the same, your diffraction disks (Airy disks) are half the width, and the image has 4 times the light coming through. In itself at low magnifications you may not be able to see any more detail as such, but because you now have that much more light to play with you can up the magnification and see more detail, and more contrasted details with the 12" than the 6". You'll note that I did not specify at the same magnification, only that the 12" will outperform the 6" in every way. Having 4 times the light is already performing better by one metric. Having twice the resolving capability is another metric, better utilised with more magnification.

Can you instead show a situation where a 6" scope of any type optically outperforms a well built well cooled 12"?

Comment: Re:Not that easy to see (Score 2) 53

by popoutman (#48885607) Attached to: Rare Astronomical Event Will See Triple Moon Shadows On Jupiter
Then your 12" dob has some pretty crappy optics. There's absolutely no optical reason why a low f/ratio reflecting telescope will perform more poorly than an equivalent diameter longer focal length scope. Yes, you may require the use of a Paracorr II to minimise coma, but that doesn't affect the area subtended by a planet's surface in the eyepiece. If you have a short focal length scope then you are of course well advised to use decent quality eyepieces that can handle a wide incoming light cone, eyepieces such as the Ethos and Delos range from TeleVue. There's no substitute for clean optics, decent eyepieces, and a quality well-figured mirror. A 12" should outperform a 6" in absolutely every way, and I've seen this proven with my own scopes.

I recently upgraded from a 200mm Newtonian with a .977 Strehl f6 mirror to a Skywatcher 12" f4.9 dob. I've since been able to resolve features on the disks of the Galilean moons, and I've been able to see the Pup (Sirius B). I've found that I still see more detail on the planets than I used to see with the 8" even when using the 12" in bad seeing. A good 12" scope will outperform *every* 6" scope, top end refractors included, on the planets when set up and built and used correctly.

As for the OP's point, you'll still be well able to see the three shadows, and Ganymede in silhouette against the cloudtops, and you'll be well able to see Io when it's in eclipse again silhouetted against the cloud tops. I've been able to see shadow transits very easily with my 70mm and 80mm ED refractors, so you should have no problem with your 110mm scope. It'll be small for sure, but still visible

I've been an observational astronomer for about 30 years at this stage, and I'm saving to get myself a nice 28" f2.7 Webster scope as my perfect scope, both for planetary and deep sky observations.

Comment: Re:Solar and sidereal time. (Score 1) 232

by popoutman (#48635387) Attached to: Ask Slashdot: What Can I Really Do With a Smart Watch?
Given that the effect of nutation is ~20 seconds over a period of 18 years, it's measureable but minute. It's circa a second difference per year, which seen per day can be effectively ignored. It was seen first with changes in latitude, and was some time before the changes in longitude were measurable.

The one second per year difference is more than 3 magnitudes different to with the 35 minutes a year that solar time varies by.

Comment: Re:Solar and sidereal time. (Score 2) 232

by popoutman (#48631089) Attached to: Ask Slashdot: What Can I Really Do With a Smart Watch?
Sidereal time does *NOT* have a variable length day. Since it's defined as the average time between successive transits of any particular star, it's *ALWAYS* 23h 56m 04s (approx, or for the decimal preferrers 23.9344696 hours). Apparent solar time does have a variable length, due to the Equation of Time - the function of the difference between a perfectly circular Earth solar orbit and the actual elliptical orbit that we follow.

The sidereal day was always much easier to time, with transit telescopes.

Comment: Xprivacy and rooted for the win.. (Score 5, Interesting) 234

by popoutman (#48474439) Attached to: Uber's Android App Caught Reporting Data Back Without Permission
Makes me very happy that I have XPrivacy installed on my rooted S4 Active, and I now have a fine-grained security model with the ability to control what apps have access to what.

It was an eyeopener to see some apps that were misbehaving or just outright being illegal. My flashlight app now only controls the LED on the rear, and cannot see any of my private details - and they earned themselves a 1-star review..

Comment: None. Use a biometric as a username only (Score 2) 127

by popoutman (#48473215) Attached to: Ask Slashdot: Best Biometric Authentication System?
Why do people constantly think to use biometrics as passwords, instead of as usernames? The fuzzy nature of digitising a biometric makes the system fall between two stools - few false negatives at the expense of many false positives or the reverse. In practice this means that you either need to scan a few times to get a good id, or run the risk of scanning as someone else. Given that you cannot change a biometric, why on earth would you use it as a single factor authentication system. It's far far better to scan a biometric then use a PIN as you can change a PIN... If you use a biometric as a single factor, you have not gained anything over the use of e.g. only a PIN, and you must allow for the possibility of false positives (equivalent of entering someone else's PIN).

Comment: Re:I don't blame WalMart Employees (Score 1) 287

The company can easily say "no, thanks" to the offer of the reduced price. After all the sticker prices are not final, they are only an offer to treat. There's nothing to stop someone negotiating a price that suits. If both parties agree to it, it's not illegal. Ergo, it's not stealing. If using fake prices as a negotiation tool, it is underhanded yes, but illegal, no.

Comment: Re:Shattered (Score 1) 473

by popoutman (#48424711) Attached to: Elite: Dangerous Dumps Offline Single-Player
If you have broken your promises and failed to make good on it - honest and free market forces mean that you'll be remembered for that and punished appropriately. Personally if I was the recipient of such broken promises I would ensure that everyone knew about it so they would not fall victim to the same lies. The internet does make it easier, and that's a very good thing for cases like this where snakeoil salesmen can more easily be outed.

Having said that - if the promise breaker made good on the restitution, I'd also make sure that everyone knew about it so that the good work done by the promise-breaker.

Comment: Re:Apparently "backers" don't understand the term (Score 1) 473

by popoutman (#48418277) Attached to: Elite: Dangerous Dumps Offline Single-Player
You may consider that changing your mind does not constitute a lie, and you may be correct in saying that. However, changing from the product as described up front at the beginning of funding to a product that has significantly changed from the original premise - that constitutes FRAUD.
I bought in on the kickstarter on the assumption - validated by the original text - that there was going to be a single-player offline game mode, that did not require always-online.
I d not want a game based on an external set of servers - I want to be able to play my game at my pace, on my own computer, without the need to phone externally for in-game items, transaction etc. Frontier Developments have shot themselves in the foot here - two-thirds of those that have already paid want offline play, and one in 5 of those that have already paid have stated that they need offline.
I've a funny feeling that the consumer protection laws will apply here, as one thing was sold pre-development, and another is being delivered. You would not be happy if you pre-bought a watch only to find that the production version, while having numerals on the face, does not tell you the time; as such I am not happy at all with this development.

Comment: Debian OS is no longer of use to me now (Score 2, Interesting) 581

by popoutman (#48416843) Attached to: Debian Votes Against Mandating Non-systemd Compatibility
My feelings on this matter? :(
I intensely dislike systemd and all of its methodology - it's not the Unix way, and I really dislike the systemd developer's attitudes towards bugfixes and other problems with their processes. Systemd is a solution looking for a problem.
As an admin in a company with something like 50,000 *nix machines, of which I have root on about 10,000 of them, systemd will not be making an appearance on any of these systems and the vendors have been appraised of this fact. Any vendor that cannot provide an alternative to systemd will not be in the running for the next phase of server rebuilds.
Personally, I think I'll be migrating all my own personal servers and the servers of my University's computer society to something a lot more useful and not requiring systemd to boot. Going to be a fun time.

Comment: Solar time (Score 1) 613

by popoutman (#48294057) Attached to: Ask Slashdot: Where Do You Stand on Daylight Saving Time?
Make it so that the average solar noon is some time between 11.30 and 12.30 on the clock. No change of clocks during the year. Exactly as convention has had it for centuries. The timezone divisions are about right.

If you need more time in the evening, then petition your boss to have differing hours of work. There's no real reason why you can't wake at dawn, be at work shortly after sunrise, lunch at local noon, and finish work and have hours of daylight left to play with.

Comment: Re:Good for them (Score 1) 558

by popoutman (#48286579) Attached to: Rite Aid and CVS Block Apple Pay and Google Wallet
Current NFC payment schemes actually in operation and not just theoretical exercises like Apple's scheme, only require the waving of the card over the reader. Nothing else required. At least the exposure is limited by most banks to a certain value above which the PIN is required. I suggest you read up on the "Visa Paywave" or "Mastercard Paypass". My original comment referred to all NFC payment types, not specifically to Apple's. Given that the Apple fingerprint sensor fails the same tests as all biometric schemes, it's still not an adequate response. At least with pin&chip, no transaction occurs until you enter your PIN, and you can easily change your PIN if required. Good luck changing your fingerprint.

Biometrics, if used, should be used as usernames, not as passwords.

Comment: Re:Good for them (Score 1) 558

by popoutman (#48283521) Attached to: Rite Aid and CVS Block Apple Pay and Google Wallet
For one, there is far less physical security. There's no physical feedback for a transaction to have taken place when the card is e.g. in a wallet or pocket. The card doesn't even need to be visible for inspection, nor does it even need to be present at the reader terminal for a transaction to take place.

I've seen a proof of concept described that bypasses a lot of the physical security that is assumed to be present with NFC payments. Take two reasonably powerful and sensitive NFC transmitter/receivers, both portable and each connected to a comms device like a rooted Android phone, give one combination pair each to two people involved in the demonstration. Put one of the aerials inside a wallet, carried in the hand with the cable hidden e.g. up a sleeve. This person would be the one "paying". The other person just need to be nearby the "mark" whose card is to be used to pay for the transaction, close enough for the card interrogation to take place. Create a channel where the received data at one aerial is transmitted by the other, and vice-versa. Then when the payment is requested, the shops' cardreader has no way to recognise that the device being waved at it is not the actual one being interrogated for the transaction. The "mark" has no knowledge that their card was just used for a purchase. The merchant has no way to know that the transaction was fraudulent.

The same type of paired-device communication will also work to get through doors that require only a wave of a card in front of it.

So, if you want to have something that can be as easily bypassed as this in your pocket, please ensure that there is a decent faraday cage around it to prevent signal leakage when you don't want it used.

Don't be irreplaceable, if you can't be replaced, you can't be promoted.

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