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Comment Spamassassin and Greylisting.. (Score 3, Informative) 269 269

Up to date spamassassin and well configured greylisting works very well for my email solution. The most spam mail comes in on mailing lists that deliberately have differing settings on them. Plus I have spam and ham training active. Rare enough to get spam into my actual inbox these days.

I've also got very little spam on my Gmail address as well..

Comment My main rig.. (Score 1) 558 558

For a 3 year old build, I'm pretty proud of how this has held up performance-wise. I've updated the gpu since I built this machine, and that's pretty much the only change since building it.

Intel i7-3930 @ 4.3Ghz,
16Gb ram,
120Gb SSD,
4x1Tb spinning HDD in RAID 1+0,
Asus Nvidia 760GTX (I think..).
Asus P9x79 pro motherboard.
Using the integrated sound, but with a PCIe wireless card.
1600x1200 Dell lcd monitor (yep, still in 4:3 land).
Closed circuit watercooling on CPU.

I have to send the motherboard away for repair as a BIOS update failed - for the second time on this board - I've already had a warranty replacement for failed bios update.

Comment Re:Please explain (Score 1) 158 158

My GPS stable:

Samsung S4 Active (personal phone).
Iphone 5s (work phone),
Galaxy S2 mini (spare phone),
GPS usb dongle for my desktop PC,
Garmin satnav device in the car,
Garmin Edge 500 bike computer,
old Garmin handheld eTrex mono GPS ~8 years old now.

Easy enough to rack up the device count when a techie for long enough and involved in active sports.

Comment Re:Bad news for a lot of people (Score 1) 649 649

Air filters are a bad analogy - as the stock ones are hugely low resistance anyway and changing for a so-called "performance" filter is anything but.

You can measure the resistance of an air filter by checking the pressure difference before and after the filter element. In all of the tests that I have seen the airflow resistance due to a stock filter is miniscule, and there is more pressure loss due to a bend in the pipe than due to the filter. Putting an ineffective filter that passes lots of grit through it, may be less pressure loss, but 80% of a miniscule number is still miniscule and has *no* measureable effect on power.

Otherwise I completely agree with you.

There's a lot to be said for a car company continuing to use a known-reverse-engineered protocol for the inter-module communications and code interrogation such as the protocol used by VAG on all of their cars. That makes things a lot easier, being able to use an inexpensive cable and software to access the same items as the main dealers.

Comment I love the EU for making non-competes illegal (Score 2) 331 331

Here in the EU, if there are terms in an employment contract that effectively mean a non-compete for X length of time after leaving that employment, they are completely unenforceable once the employment contract is terminated. The key terms are "contract" and "terminated". The contract no longer exists legally once the employment is terminated.

If a company wants non-compete methods, then they have to request that the newly-ex-employee sign a new contract to not compete with the previous employer's competitors, and in every case that I have heard of, the monetary terms for that non-compete had to be very very generous in order for the newly available employee to not work for the next 6 to 18 months in the business. Some in this situation went on training courses to stay current, others branched out into differing areas of work, all while getting handsomely paid not to work for the competitor.

Amazon have their head up their ass regarding the treatment of their employees for a long time in the US, and it'll come back to bite them. At least in the EU the employee protection legislation prevent such entities from taking that level of advantage of their employees. I'll be glad if/when karma comes back to burn Bezos and gang over their unethical actions and general mistreatment of their staff.

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

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) 304 304

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 53

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 53

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) 232 232

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) 232 232

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) 234 234

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) 127 127

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) 287 287

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.

"Is it really you, Fuzz, or is it Memorex, or is it radiation sickness?" -- Sonic Disruptors comics

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