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User: EvanED

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  1. Re:Grinding your eyeball? on The U.S. Navy's Doctrine of Laser Eye Surgery · · Score: 1

    Yes and no.

    In the case of poor eyesight, you're not usually facing the potential for death. It could very easily be that a risk for saving you life might be okay, but the same or even smaller risk for not having to deal with glasses wouldn't.

  2. Re:Can these these chips do any calculations? on Frozen Chip from IBM hits 500 GHz · · Score: 3, Insightful

    at light speed, an electron wouldn't have enough time to make it through the long circuit paths before the next clock cycle.

    It doesn't need to go through the long circuit path...

    In fact, signals haven't gone through a whole path since (at the latest!) the 286. The processing is already divided into stages, and it only passes through one stage in each clock cycle. (Look up pipelining.)

    It would be theoretically possible to design a chip that operated at a lot higher clock speed just by making the stages shorter.

    Think of an old fire fighting bucket brigade. If you have one person carry the bucket from the source to the fire, you're gonna have a hard time getting control. If you add people, at some point you can add people until everyone just passes the buckets down the line without moving. If you continue to add people, the buckets will probably not move a lot faster, but you'll have more buckets "in flight" at any given time. Note that the time it takes any given bucket to get to the fire has actually INCREASED because there's overhead in the handoffs and everyone isn't synchronized, but you're gonna get a lot more water on the fire than if you just had one person. You'll also see a bucket being thrown onto the fire much more frequently.

    In some sense, the buckets are like instructions, the firefighters are like pipeline stages, and the frequency with which any given person changes buckets is like the clock speed. In a processor, you can add more stages to your pipeline and make it so that each stage has each instruction for less time. There is a limit to the minimum time, just as there is for the firemen (you at least have to grab the bucket from the person before you and let go when the person in front has it, and adding more people to the line won't help at all with that overhead), but the limit isn't the time from fire hydrant to fire.

  3. Re:Chances and Cheating on Chinese Students' Cheating Techniques - Don't Try at Home · · Score: 1

    Way to see the tree but miss the forest. While if you do poorly on the GREs you have to wait another year (not totally true; they're given at least twice a year), the situation is very different from what it sounds like there.

    That paragraph says that the admission system there relies essentially exclusively on that test. ("Chinese college admissions officers don't look at your high school grades, personal interviews, recommendations or essays in making their decisions.") This is a VERY different situation than the GREs here. While they are a factor, ask almost any admissions officer and they'll say that it plays a relatively minor role. A perfect score doesn't get you admitted, and a low score doesn't necessarily get you disqualified. This is even more true amongst the "better" universities, as they are often looking for undergraduate research experience. Carnegie-Mellon doesn't even look at your GRE score even if you send it to them.

    As far as undergraduate goes, it's not like the SAT either. Go around $BIG_NAME_UNIVERSITY and you'll find people who have low scores, and conversely it's not hard to find people with 1600s who were rejected from $BIG_NAME_UNIVERSITY. (At least, not much harder than finding the people with the 1600s in the first place.)

  4. Re:Not Digital SLRs... on Prototype System Blocks Digital Cameras · · Score: 1

    I'd be shocked that their mechanical engineers aren't drooling over the opportunity to design a new mechanism and probably have already proposed many tentative solutions that aren't ready for prime time production.

    But that's the beauty of the idea! There's nothing new mechanically, only electrically. Everything that needs to happen mechanically has already been done... mirror lockup has been around forever, the 20D can shoot at something like 5 fps so it can recycle the shutter in at no more than 1/5s, and that's all that needs to happen. (And a 1/5s delay after button press is already on par with most P&S digitals.)

    It might even be possible to do this with just a simple reprogramming of the microcontroller on the thing... all the connections are already there: sensor to processor, processor to LCD, processor to shutter, and processor to lens.

    The digital SLR product lines are just starting to take shape for consumers. I doubt many professionals would care for this new feature because they already know how to take great pictures without it.

    I think this is the key here.

    I think you'd see professionals very hesitant to change most of the time. About the only time I could see something like this being useful in the pro realm is for photojournalists if they need to hold the camera over their head to get above a crowd or something like that.

    Will the mechanism work fast enough to close to bring the mirror down, close the shutter, then do the exposure which includes another open and close of the shutter, and then return the mirror back up and shutter open again for a single exposure? Seems like it could be brutal on the mechanism if it weren't designed for that. I'm not very familiar with SLR mechanisms beyond what we've already discussed.

    The mirror wouldn't move during this process. You'd hit a button to turn on a live LCD display, and the mirror would go up then. The shutter would also open. Both need to happen, or there's no light falling on the sensor. When you shoot, the shutter closes, the sensor is reset, the shutter opens, exposes the shot, closes, and then opens again to continue the live display. (Or, alternately, the mirror pops down and the live display ends. Also, I left out the stopping down of the lens which happens before the shutter opens for the picture.) Again, there's nothing here mechanically that hasn't been done for a couple decades at least, with the exception of the connection from the sensor to the LCD.

    Actually, now that I'm typing this, I can see a potential snag. I don't know where the meter and AF systems are located in the camera. It's very possible that they are above the mirror, in which case flipping up the mirror to expose the sensor would cause them to no longer work. To test this, I pulled out my Rebel XT and set it to mirror lock up. The way this works is you press the shutter once to flip up the mirror, then again to expose the image. A quick experiment confirmed that the exposure and focus are set at the first button press. Whether this is a matter of a technical limitation or just a decision as to which would be more workable from a usability standpoint I don't know.

    So I don't know how difficult this would be to overcome.

  5. Re:MS Resources come with bagage! on Gates' Replacement says Microsoft Must Simplify · · Score: 1

    Most of the components I picked out were one or two steps down from top of the line. I got an Athlon 2000 at a time where there were probably 2400s, I got a GeForce4 when the Radion 9500 and 9700 (or whatever ATI card was released at that time) were out and quite a bit better. About there only place it competed on the same level as most high-end products was the RAM.

    I also put quite a bit of money into a couple things that don't count for performance. I got a good TV tuner card (that was 120 bucks or so), wireless keyboard and mouse set (100), 19" monitor (350), quite a bit nicer than average case, etc.

    It was a quite GOOD system, but it wasn't top of the line.

    (BTW, this was graduation gift.)

  6. Re:Not Digital SLRs... on Prototype System Blocks Digital Cameras · · Score: 1

    It does seem that they could create a new prism that splits to the view finder, CCD & shutter, and a third CCD for the screen. I wonder what additional aberations this would create?

    I don't think you'd want to do that. The biggest consequence as compared to an SLR would be that you're no longer getting as much light to EITHER the viewfinder (meaning it's harder to see what's in focus... and with the damn cameras nowadays coming without a split-image, microprism, etc. screen it's hard enough already) or the actual sensor for the piture. At least I find myself usually wanting more light so I don't get camera shake, so I wouldn't go for this situation. I'd take one light path any day.

    The one thing that I don't see why they can't do is to have a button that will flip up the mirror, open the shutter, and feed the sensor data to the LCD. I could see the low end SLRs not having this feature, but if I were Canon I would probably look into adding it to the xD line (10D, 20D, 20D). The first part is already done; even the Rebel XT has mirror lockup. (And the original Rebel if you hack it!)

  7. Re:Again, won't work. on Prototype System Blocks Digital Cameras · · Score: 1

    On second thought, I think the situation is better outdoors then I said. You'd probably get 4 stops above a brightly lit room if the day's party cloudy and the sun is behind a big cloud. You'd probably get another 3 or 4, not 1, if the sun's out.

    (However, I still maintain that there are few photos taken at anywhere near that shutter.)

  8. Re:Again, won't work. on Prototype System Blocks Digital Cameras · · Score: 1

    I bet that if I were to take statistics on my photos (I have a Rebel) the average shutter would be about 1/100th of a second. It'd certainly be a HELL of a lot closer to that than it would be to 1/8000th.

    Some quick calculations. A typical indoor photo on my Rebel typically meters at about 1/60th and f/4 at, say, 200 ISO. (I'll be generous... I usually go to 400 or 800 for indoor shots.) To get proper exposure at 1/8000s:

    - bumping up to 3200 ISO would give you four stops to play with. Putting all of that into a shorter exposure, you can get to 1/1000s. [Double the ISO and you double the sensitivity, so for the same exposure you need to close one stop or halve your shutter.]

    - this gives you three more stops, which means you need to widen the aperture to f/1.4.

    Personally, I don't own a lens that will do f/1.4. (Of course, I also don't have a camera that will do 1/8000s.) The fastest lens I have is the 50mm f/1.8. There are a couple f/1.4 lenses, so getting 1/8000s would probably be possible. There is even an f/1.2 lens (for a couple grand), which would give you another third of a stop to play with.

    Outdoors the situation is better for you, as you get I would guess 4 more stops of light. This would allow you to close to f/4 and drop to 1600 ISO for instance. If it's really sunny, you might be able to get another stop.

    That said, unless you've got pretty specific conditions, I can guarantee that you're not shooting 1/8000. You'd be better served to drop to 1/2000 (at least! that's still incredibly fast) and lower your ISO (for less grain) or close your aperture (so your depth of field doesn't suck). I know sports photographers may want the faster shutter, and there are probably a few other fields where it's important.

  9. Re:My question is... on Prototype System Blocks Digital Cameras · · Score: 1

    You're a little too narrow minded here. We're not talking emergency communication as in the fire dept are trying to talk to each other while they're putting out the fire, we're talking emergency communication of a different class. The canonical example seems to be the doctor who's on call and needs to be able to receive a call in case a patient comes in with an emergency. You could say someone like that shouldn't go to a theatre, but I think that is very unduely restrictive because people like that are often on call for a substantial portion of their time, and should be able to enjoy themselves as far as they can.

  10. Re:Battery Life on Origami Feedback Mixed, says Samsung · · Score: 4, Insightful

    IMO, it needs to have at least 8 hours of battery life at the minimum.

    Why? Your typical work day is what, 8 hours. Are you gonna be using the thing all day? Samsung's website says that the battery life of the Q1 should be about 3.5 hours. Even if you're using the thing half the time, that should be plenty. And it seems to me like the half would be high.

    There are times when a longer battery would be really nice, like for plane rides and stuff, but for day to day operation, 3.5 hrs isn't low enough to be a deal breaker. I mean, laptops have battery lives of under that often, and I think you'd be hard pressed to find someone say they're
    not useful.

  11. Re:MS Resources come with bagage! on Gates' Replacement says Microsoft Must Simplify · · Score: 1

    I figure now's the time to end that since Vista's gonna require everyone to upgrade their gear anyhow.

    Where the heck does this conception come from?

    I have a four-year old computer. I think most people on /. would agree that, in computer time, this should qualify for senior discounts. When I got it, it was a good computer, but couldn't remotely be considered top-of-the-line. (I paid about $1500 for it I think.) I've made one upgrade to the computer's horsepower, and that was to increase RAM from 512 MB to 1,5 GB (I'm in Norway now, so I'll use their system of notation for decimals). (That was another $100.) Vista's upgrade advisor thing says my hardware is fine to run any edition of Vista, with Aero. Furthermore, that extra RAM isn't necessary for a good rating. Finally, at least one review said that it runs on hardware thatæs well under what they recommend.

    Sure, some people would have to upgrade to get Vista, but they aren't early adopters or they'd be set now, so they'd be unlikely to get Vista even if their hardware was good.

    (The big exception to the "four-year-old computer is fine" thing is laptops. Even so, probably anything with 512 MB RAM would work.)

  12. Re:If Complexity Kills.... on Gates' Replacement says Microsoft Must Simplify · · Score: 3, Interesting

    I'd almost guarantee that if you removed the API then .Net would stop working because it's implemented on top of it. It probably is implemented on top of COM as well.

    And anyway, the chance that you'd have NO such applications is virtually nil.

  13. Re:Microkernel anyone? on Linux 2.6.17 Released · · Score: 1

    If you want to add a new driver or even change one, it pretty much takes co-opting the entire kernel tree, or compiling the driver live against the current kernel, or having pre-compiled modules against every possible kernel out there.

    But same deal with a microkernel if you don't have a stable ABI. You'd still have drivers that work under one versoion not work under another because the interface changed.

    Now, I don't know enough to make a statement regarding this either way, but it's possible that having the drivers in userspace might make it easier to have a stable ABI, but to frame the debate as between uKernels and non-microkernels (and as a side note, it's no longer really micro vs. monolithic) is skirting the real issue which is the ABI stability.

  14. Re:Slashdot is going to hate this... on How iTunes Hurts Weird Al · · Score: 1

    Apple?! Apple's doing enough in my mind just RESISTING the RIAA's efforts to raise the cost to $1.19 or whatever they've been trying to do!

    (Also, there are other accounting issues that make a bigger difference than the difference in price between a CD and iTunes album.)

  15. Re:Cuplrit? on How iTunes Hurts Weird Al · · Score: 1

    Al might not have had a choice. I think almost all that music went up there on iTunes under existing contracts, which, of course, aren't really negotiable anyway.

  16. Re:Weird Al, an Artist? on How iTunes Hurts Weird Al · · Score: 4, Insightful
    Would you RTFA?

    Al's not really complaining. Someone asked him what medium gets him the most money, and here's what he had to say:

    "I am extremely grateful for your support, no matter which format you choose to legally obtain my music in, so you should do whatever makes the most sense for you personally. But since you ASKED... I actually do get significantly more money from CD sales, as opposed to downloads. This is the one thing about my renegotiated record contract that never made much sense to me. It costs the label NOTHING for somebody to download an album (no manufacturing costs, shipping, or really any overhead of any kind) and yet the artist (me) winds up making less from it. Go figure."


    He's a little sarcastic about it, but that IMO doesn't come close to "complaining".

  17. Re:He's not getting ripped off on How iTunes Hurts Weird Al · · Score: 3, Insightful

    There are a couple possible reasons they can't do what you say.

    In Weird Al's case, he very well may be in a "you produce x number of albums for us" contract and only partway through. So he's contractually prohibited from going independent.

    In the case of a new artist, you have to admit that the record companies DO do stuff to get you exposure. For instance, it's VERY hard to get on most radio stations if you don't have support from the labels.

  18. Re:It's a little worrying... on Microsoft to Turn to Driver Quality Ratings System · · Score: 1

    That's not really being fradulent in the way the GP was talking about though. You could use it for the first part (the "their machine can't run the latest FPS any higher than 60 frames per second"), but it still isn't being completely illegit because it IS a problem. (And if MS has something in place that at least severly de-weights multiple submissions from the same person, that would take care of that issue anyway.) It doesn't help at all with the second bit ("Or how can we be sure that nVidia users won't go gang bang ATI's driver ratings or vice versa") because those nVidia users would have to install the ATI drivers. Even if that's possible, I don't think many would.

  19. Re:It's a little worrying... on Microsoft to Turn to Driver Quality Ratings System · · Score: 1

    Um, because it's not a "go rate the driver system". It's a "when the driver crashes, Windows gives you an opportunity to report that" (as it does now) thing, then they collect the numbers or do some other analysis to determine if it's revoked.

    To falsify this, you'd have to reverse engineer their error reporting scheme.

  20. Re:Here's the scam on New IP Treaty Looming? · · Score: 1

    Okay, I stand corrected. /. needs a -1, Wrong moderation for my original post...

  21. Re:Repackaged content deserves copyright?! on New IP Treaty Looming? · · Score: 1

    It would only affect churches whose copies of the Bible are derived from your broadcast.

    Sorry to burst your otherwise great idea though.

  22. Re:Here's the scam on New IP Treaty Looming? · · Score: 2, Insightful

    By my understanding, treaties don't actually do anything domestically. If the US signs and ratifies a treaty, it doesn't actually do anything except demonstrate the country's commitment to the treaty. The Congress would then have to pass a law to make US statutes consistant with the treaty.

    People who know more about this than I, is this accurate?

  23. Re:Stupid on New IP Treaty Looming? · · Score: 1

    The Betamax case had the Court ruling that there was nothing to prohibit recording broadcasts. However, the Court also clearly stated that this wasn't an inherit right, and that Congress could introduce legislation banning it if they wanted.

  24. Re:beyond what the human eye can see? on HDMI Spec Upgraded To Support 'Deep Color' · · Score: 1

    Video is not sampled at 48kHz, that is more typical of audio.

    Yeah. The 24-bit, 48 kHZ is DVD audio; I brought it up as an analogy. In some sense the bit depth is the same idea in each instance 24-bit in audio, now up to 48-bit per pixel in HDMI; both describe how much data is used to represent each point in time. With HDMI you have to add an additional factor of the number of pixels though, and that has no analog in audio.

    (And in some sense the sample rate of audio is analogous to the frame rate of video, though they are vastly different values.)

    Sorry, I should have made it clear that I was talking about audio there. Some things that make sense when you're typing them out don't make sense to other people because you don't write everything you're thinking down.

  25. Re:um, fusion bombs aren't new on Hawking Says Humans Must Go Into Space · · Score: 1

    Did you read his comment? He said a fusion bomb without a fission trigger. The article you quote says in the caption of the illustration "a fission bomb uses radiation to compress and heat a separate section of fusion fuel."