Wikipedia:Reference desk/Archives/Computing/2014 September 9

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September 9[edit]

Need to clone Win7 drive[edit]

I have a Windows 7 machine a few years old. I got a window from Windows saying my one and only hard drive on which my C drive lives reported a failure and that I'd better back up. The computer still works fine, for now. This drive is 500 GB. I bought a new 1 TB drive which should arrive in a few days. I want to know if there's anything wrong with my following plan of action. 1) Connect the 1 TB drive and format it, clicking Yes bootable, one partition for the whole thing. 2) Restart the computer booting from Clonezilla on CD. Choose device to device. Of course the 500 GB as source, the 1 TB as destination. 3) Disconnect the 500 GB drive and reconnect the 1 TB where the 500 used to be.

Additional question: Will Windows notice it's on a different drive and phone home next Windows update and shut down on me? 75.75.42.89 (talk) 00:58, 9 September 2014 (UTC)[reply]

I did almost exactly this a while ago when I switched to an SSD (I will never look back). Windows 7 didn't even mention that the drive was different, and my system is as it was (but much, much quicker). 217.158.236.14 (talk) 09:13, 9 September 2014 (UTC)[reply]

Ditto that. I don't remember which software I used, but as far as problems go, I remember it creating a smaller partition on the larger drive (same size as the source drive). That, however, was easy to fix by extending that partition to cover the remaining unpartitioned space. I never had any problems after that (and it's been a couple years).—Ëzhiki (Igels Hérissonovich Ïzhakoff-Amursky) • (yo?); September 9, 2014; 18:25 (UTC)

Is your Windows OEM? Many OEM versions will have a software lock and detect if the hardware was changed. KonveyorBelt 23:52, 9 September 2014 (UTC)[reply]

Someone on microsoft.com asked a similar question. Relevant part frrom the answer (from a community moderator): "If I buy a Hewlett Packard with OEM Windows 7 pre-installed onto a hard drive and then later REPLACE that hard drive with one that is better, does that invalidate my OEM Windows 7 licence?

No, but you will have to reactivate your installation of Windows 7. " Then another answer on how to actually do that: Start->slui.exe 4, Select country, select phone activation, hold for real person. 20.137.2.50 (talk) 14:38, 10 September 2014 (UTC)[reply]

index.html etc.[edit]

Among our perennially popular pages are the index.php and index.html pages, with hit counts presumably fueled by bots instructed to view websites' index.php and index.html pages. A similar page, index.htm, works the same way, but it has far fewer hits, so I'm guessing it's used as a page name by far fewer websites. Why is this true? Or am I incorrect? Nyttend (talk) 02:38, 9 September 2014 (UTC)[reply]

When a browser tries to access a web address a request goes to the web site's web server giving the path of the required page. This path may be indicate a directory (folder) rather than a file. In this case the web server software needs to know what to do and it is told this in its configuration file. In the early 1990s on the first web site I set up using NCSA HTTPd the configuration specified a file name to be assumed at the end of the path and the default name happened to be "index.html". When Microsoft came into this game they were still using (requiring?) three-character file name extensions so in IIS they made the default "index.htm". These days web servers are far cleverer (though I am not) and the configuration can be a list of file names to be looked for in order of preference: Apache[1], IIS[2] and Nginx[3] However, the default names of 20 years ago are still lingering on with the name used depending on the original web server software which again depended on the original operating system. Thincat (talk) 11:05, 9 September 2014 (UTC)[reply]
Couldn't the index.php and index.html articles be very popular among students and learners? Sure, there might be a bot effect, but I also think it's reasonable that those pages are genuinely popular among humans... from the other angle, I think a bot that's looking for index.php files on web servers, and instead loads our article, is a weird situation, and perhaps the mark of a poorly-designed bot. I mean the URL for the article is not actually the file path on the server, right? SemanticMantis (talk) 14:20, 9 September 2014 (UTC)[reply]
There is no doubt that "index.htm" comes about from older versions of Windows where the filename extension was limited to three characters. (Hence ".jpg" instead of ".jpeg", etc) That was never a problem for Linux-based servers - but there was a period where some servers could support ".html" filenames. These days, I'd expect very few web sites to need to use ".htm" - but I'm sure there are people who got their brains locked into the shortened form during that period of crappiness who haven't switched over - and perhaps a few old websites that just never got rebuilt - maybe a few old "How to Build a WebSite for Complete Newbs" books that still use ".htm" that are teaching people bad habits.
It's possible that:
  1. People are searching for articles about "index.html" because that's the modern form - and far less often searching for "index.htm".
  2. Search engines work by following links...they wouldn't know about either of our articles unless there were links to them from someplace else. Probably, the number of other pages (both external websites and internal Wikipedia articles) that link to these pages is heavily skewed, resulting in more bot searches finding one than the other.
  3. There are nine WIkipedia pages linking to index.html and only three linking to index.htm...and of course one of those is the link from this very page - so discounting that one, there are four times as may routes to index.html than there are to index.htm. Furthermore, the only other links to index.htm are from the reference desk main page(?!?) and from some dusty old archive of the wikipedia front page talk page. Hardly anyone will click on either of those links. But the eight remaining links to index.html includes one from "Wikipedia:Most read articles in 2008"...which suggests that this was a HUGELY popular page...in fact, it was the fifth most popular page on Wikipedia that year with 4.3 million hits. That's going to ensure that a TON of web pages outside of Wikipedia link to it...which drives traffic, and search engines to that redirect.
  4. That is a mistake...that people are somehow arriving at: https://en.wikipedia.org/wiki/index.html - expecting that to be the 'root' of the Wikipedia home page. More interestingly, if you go to https://en.wikipedia.org/index.html, you hit a page with a big 404 warning - which helpfully tells you "Did you mean to type https://en.wikipedia.org/wiki/index.html?"...then redirects you there 5 seconds later. So anyone who tried to get to Wikipedia's main page using "index.html", "index.php" or "index.htm" gets redirected to the article! So if search engines are spidering for the ".html" extension - or if people are incorrectly pointing their web page links at the "index.html" file instead of using just "https://en.wikipedia.org" then they'll arrive at the "index.html" article page...which is pretty weird.
SteveBaker (talk) 15:01, 9 September 2014 (UTC)[reply]


But why that would alter the spidering behavior of search engines and such.
Because for a vast number of web sites: http://XXXX/index.html (or .php or .htm) takes you to the same page as http://XXXX - so it's quite possible that EITHER a lot of people are typing links to Wikipedia with "/index.htm" on the end - which would drive spidering software to visit and/or count the index.html article a disproportionately large number of times for such an obscure topic...OR...there are poorly written spidering bots out there that search for the "http://XXXX/index.html" page either instead of or as well as the bare "http://XXXX" URL. My bet is that it's a bit of both.
SteveBaker (talk) 15:34, 9 September 2014 (UTC)[reply]

I think this is actually an amazingly interesting finding - and quite a worrying one. The fact that the "index.html" page was the second most popular actual article in 2008 (only fractionally less popular than the article about the 2008 Olympics - and significantly more popular than Sarah Palin!) clearly suggests that people were totally confused and got there by mistake. 4.3 MILLION people were confused by this! That's an astounding number. It should be fixed.

To that end, I posted a query at the village pump in an effort to get some eyes on getting this fixed. SteveBaker (talk) 15:37, 9 September 2014 (UTC)[reply]

Hard maximum for Firefox[edit]

Does Firefox (or Chrome or IE) have a maximum resolution, after which it will no longer work (assuming, of course, that the native resolution of the monitor is not an issue)? I've been playing with it, but every time I get to 8k pixels in a single direction, the whole window turns black, meaning that I can't read or do pretty much anything with said window. — Crisco 1492 (talk) 05:31, 9 September 2014 (UTC)[reply]

I could imagine your graphics card running out of memory, or hitting an internal limit on the size of a texture map (for example). These days, both Firefox and Chrome browsers use the graphics "GPU" to speed up image composition - so the internal limits of your GPU would impact their ability to render large windows (I'd be kinda surprised if IE did that - but it's possible). 8k pixels sounds like the right kind of size for hitting a GPU limit with an older (or crappier) graphics system. I know that it's possible to disable 'hardware compositing' in Firefox...if you do that and find that it fixes the problem - then maybe that's the reason. Since monitors that can reach 8k pixels are exceedingly rare and exotic - I'm curious about how you're actually testing this...it could easily be that your test approach is the real culprit here. SteveBaker (talk) 14:36, 9 September 2014 (UTC)[reply]
  • I'm playing around with Infinite Screen. After playing around a bit more, I think the "hard limit" isn't quite 8k (I was at 9.5k at another website). GPU might be it, and this is a (relatively) old card (GeForce GT 630M). As for why I'd want even more pixels... there's more where this came from. — Crisco 1492 (talk) 14:45, 9 September 2014 (UTC)[reply]
Excellent. Turning off the hardware compositing was enough to stop the window from going all black. — Crisco 1492 (talk) 14:51, 9 September 2014 (UTC)[reply]
Yeeeeaaaaahhhh!! The GPU-limits theory must be the right one!
The max resolution for various nvidia cards seems to be either 8k or 16k - there are a few older cards still in use with a 4k limit - but in theory, anything that supports DX11 and/or OpenGL 4.1 should be capable of 16k. But it's very possible that 8k is the limit on your 630 hardware. The limit probably only applies to each element that the HTML renderer has to composite - so it's perfectly possible that you have a 9.5k window with an 8k image embedded in it that works OK...but in general, it's going to be tough to get arbitrary windows to work beyond 8k. Graphics cards that support 16k are becoming more and more common - so a graphics card upgrade should get you up to 16k, but it's an ungodly amount of memory - so if you expect I'd expect to be doing this a lot, you'll want to get one with 4Gb of GPU memory and not cheap-out on a 1Gb or 2Gb card. If it has to swap such large textures into and out of the GPU, it's going to be slow. SteveBaker (talk) 16:20, 9 September 2014 (UTC)[reply]
  • An ungodly amount of memory is right... no, probably won't need to upgrade just yet. Getting up to 8/9k is already plenty for most needs. Thanks for the feedback! — Crisco 1492 (talk) 16:24, 9 September 2014 (UTC)[reply]
On Windows, AFAIK, IE has had some support of significant of GPU composting acceleration enabled by default since Internet Explorer 9 [4] (also check our article), which was publicly released as a stable build on 14 March 2011. This compares to Firefox 4 [5] [6] (also our article again), publicly released as a stable build on 22 March 2011. And I think [7] (bit confused about Chrome's history here though, see e.g. [8] [9] [10] Chrome 11, which was I think publicly released as a stable build on 22 April 2011 [11] (our article isn't very useful for any of the Chrome stuff). IE's support for WebGL (also other graphics related stuff like SVG) was I think fairly late, but this doesn't seem to be what's being discussed. Nil Einne (talk) 01:12, 11 September 2014 (UTC)[reply]

Choosing a pocket-sized camera to take good photos[edit]

I'd like to learn to take better photos than my phone can manage, and I'm thinking of buying a camera, but I've heard only an SLR would be configurable enough to learn Real Photography. Thing is, the size of even a small SLR puts me off. Compared to my phone, they are some serious luggage. What I really want is something near the size of my phone, but with good build quality, a physical zoom lens even if not a swappable one, and most importantly, no noticeable lag as I turn it on, focus, or take the shot. Do cameras like that exist, and if so how should I choose one? Thank you. 87.1.125.37 (talk) 14:44, 9 September 2014 (UTC)[reply]

How are you defining "real photography"? Nimur (talk) 15:18, 9 September 2014 (UTC)[reply]
(OP) I was being sarcastic about my own ignorance. At this point I don't know enough about taking pictures to know what is essential vs what's too esoteric to matter much. 129.67.117.206 (talk) 11:26, 10 September 2014 (UTC)[reply]
(OP) I have a smartphone, which takes pretty nice pictures and okay videos outdoors in good light of things that won't run away as I get closer, but is a useless waste of time after dark or under strip lights, and has no physical zoom lens. It also has way too much lag, particularly when launching the camera app, so that subjects move away before it's ready to use. Small children love to pose, but not for long... There are too many variables involved in picking a better camera for me to make a good choice with my current level of ignorance, and I'll need to practice with something more configurable in order to learn, but I know I'd lose motivation to work with something that's a hassle to always carry around. Maybe once I know how to use it, I'd be fine with something that needs its own backpack just to hold all the bits, but not right now. Hope that makes more sense. 129.67.117.206 (talk) 11:42, 10 September 2014 (UTC)[reply]
If I understand the spirit of your question, you might look at Micro_Four_Thirds_system cameras. Many people seem to think they can strike a nice balance between size, price, and "real" photography (swappable,zoomable lenses, playing with aperture and timing, etc.) See also this overview magazine article [12]. SemanticMantis (talk) 15:32, 9 September 2014 (UTC)[reply]
(OP) Thanks! That's the sort of thing I was blindly stumbling towards. Actually though, I just typed "pocket camera" into Google, and the third hit was the Blackmagic Pocket Cinema Camera. It looks ideal - designed for video as well as stills, part of a system that I can dabble in as and when I dare, but on its own with no extra lenses, it fits into my jacket and is still configurable. Annoyingly though, I've just missed a half price sale that ended on 31st August. Think I might wait for the next one. 129.67.117.206 (talk) 11:22, 10 September 2014 (UTC)[reply]
There are a couple of good articles from NASA (sorry - I can't find the URL right now) about cameras they send to Mars and places like that. They point out that the current push towards higher and higher resolutions is largely pointless - and even though money is no limitation for them, they often go for lower resolution cameras. This is somewhat counter-intuitive. The idea is that higher the resolution of the sensor (4Mpixels versus 2Mpixels...or whatever) the smaller each pixel is on the little electronics chip at the heart of the camera. Smaller pixels mean less light is gathered at each pixel - which means that for a given lens size, the shutter has to stay open longer in order for enough light to be gathered...which means blurrier photos! So going for excessive megapixel numbers isn't necessarily a good idea. What you want to take good pictures is a good lens...a LARGE lens with lots of light gathering capability - and an appropriate resolution for your intended final application. So finding cute, small cameras and cellphone cameras with crazy-high megapixel numbers and a lens that's a quarter inch across is generally a bad idea. You want a physically large lens and a more reasonable megapixel number for the kind of use you're going to be using this camera for.
Cellphone cameras have liitle or no optical zoom capability - so they make up for that by pretending to zoom by cropping the photo! This means that they need a ton of resolution so they can zoom into distant objects. It's better to have an optical zoom lens (or switchable lenses) so that the entire resolution of your sensor is being used all the time.
If you're planning to take portraits in bright light and blow them up to poster size - then you'll need all of those megapixels - and you can put lots of light into the scene with big lights and diffusers - and the subject is sitting pretty still, so you can use long shutter times. If you want a really good photo of a race car zipping past and you're going to put it onto a web page, then you need short shutter times to capture the fast motion, you don't have much control over the lighting - and you really don't need much more than 1 Megapixel because more than that takes too long for most people to download. So a lower resolution camera with a big lens is needed. Sadly, there really isn't a "one-size-fits-all" answer. With old-school film cameras, you could fix this problem using different film speeds - but with digital cameras, you don't have that control. SteveBaker (talk) 16:40, 9 September 2014 (UTC)[reply]
User:SemanticMantis has a good point. I would suggest the Olympus Pen line. Although they are SLR cameras, they are fairly small, especially as they lack optical viewfinders. (For me, an optical viewfinder is very important, and as Olympus has ceased making cameras that have them makes me want to switch to a different manufacturer when my Olympus E-620 SLR eventually breaks down, but that is beside the point.) The full E-P cameras cost nearly as much as full-sized SLR cameras, but the E-PL cameras are smaller and cheaper, and the E-PM cameras even more so. For an example, you might consider the Olympus PEN E-PM2. JIP | Talk 18:13, 9 September 2014 (UTC)[reply]
User:SteveBaker is certainly right about the tiny cameras with a huge number of pixels. Every one of those that I've seen makes pictures that are horrible compared to my 6MP DSLR. But you can adjust the ISO on digital cameras, at least good ones. Bubba73 You talkin' to me? 18:50, 9 September 2014 (UTC)[reply]

And speaking of viewfinders[edit]

When I bought a digital camera a few years ago, two of my requirements were (1) a zoom lens and (2) an optical viewfinder, the latter because I didn't want to have to refocus my eyes on the little screen in order to frame the pictures; in addition I later realized that the screen is hard to use in some lighting conditions. However, I found that the optical viewfinder did a poor job in showing exactly where the edges of the photo would be, so if I cared about exactly what was in-frame, I had to use the screen anyway (or postprocess the picture later). In addition, the camera has a capability to zoom digitally beyond what the zoom lens will do, and of course the optical viewfinder does not reflect this; if I want to use the capability I have to use the screen. Also, the zoom lens is powered and goes in discrete steps, when with my old film camera I was used to being able to zoom exactly to the amount I chose by how far I pushed the mechanical lever. On the other hand, the camera is a great deal smaller than the film camera was.

So I'm wondering: are there any cameras these days with a digital viewfinder that you use like an optical one, by holding the camera to your eye and focusing at infinity? (It would have a miniature screen inside, and would show exactly what is in-frame.) And are there any pocket-sized cameras with a mechanically operated zoom lens?

(No, I didn't think so. Why would anyone want anything like that?) --65.94.51.64 (talk) 18:33, 9 September 2014 (UTC)[reply]

Many such cameras exist. While Canon and Nikon are still holding on to optical viewfinders, other companies like Olympus and Sony are moving to digital viewfinders only. The Olympus Pen line I mentioned above has no viewfinders by default, but have digital viewfinders as optional extras. The new Olympus OM-D SLR cameras, which are very much the same as the Pen cameras but larger, with better controls and more expandable, have digital viewfinders as standard. And as far as I've understood, the digital viewfinders on all these SLRs work the same way as in conventional SLRs with optical viewfinders, i.e. what you see in the viewfinder is pretty much exactly what you get in the picture. The framing will be the exact same regardless of whether the viewfinder is optical or digital. What I like about optical viewfinders is that there is no delay or lag whatsoever, and the vision I see through them is continuous with no pixelation or other distortions. On the other hand, digital viewfinders do have the advantage that they can show you exactly how the final picture will be, not just what the camera is actually seeing at the moment. And as all these cameras are SLRs with changeable lenses, you can zoom the lens by hand exactly as much as you want, not electronically in discrete steps. JIP | Talk 18:45, 9 September 2014 (UTC)[reply]
I think there's no such thing as an SLR without an optical viewfinder. The only reason for the reflex mirror is to support an optical viewfinder. -- BenRG (talk) 23:17, 9 September 2014 (UTC)[reply]
When I wrote "SLR camera", I was actually meaning system camera. It's just that they're commonly called "system cameras" (järjestelmäkamera) in Finnish and SLR cameras in English, although the terms aren't exactly equivalent. Sorry for the confusion. JIP | Talk 04:21, 10 September 2014 (UTC)[reply]
One note: The 'digital zoom' feature operates by cropping the image - and (possibly) resampling it to whatever resolution you asked for. If you care about your photography then you'll be using "RAW" image formats and you might as well just turn off the digital zoom and crop the image yourself using GIMP or Photoshop or whatever. That way, you can continue to use the optical viewfinder.
If you can't tell where the edges of the photo will be in the optical viewfinder then (with digital zoom disabled) I suggest you take some test photos. Line up the edges of the viewfinder with some known object (like a row of windows in the wall of a large office building), count the number of windows in the viewfinder, take the photo, then look at what windows came out in the photograph. You'll be able to get a very clear idea of how much of the image was cropped by the viewfinder (or how much you could see in the viewfinder that didn't end up in the photo). Once you have that mental image of what's going to make it into the shot, it's relatively easy to frame your pictures well using the optical viewfinder. SteveBaker (talk) 18:51, 9 September 2014 (UTC)[reply]
In the three film SLRs and two DSLRs I've had, the photo is always a little bigger than what you see in the viewfinder, by a few percent. I think that is true for almost all cameras except for some very expensive ones. But with that, if it is in the viewfinder, it is in the final photograph. Then, as someone said, you can crop it a little, if needed. Bubba73 You talkin' to me? 19:00, 9 September 2014 (UTC)[reply]
Half a year ago, having broken my old camera, I was disappointed at the slim pickings among cameras with real viewfinder, so settled for a Nikon Coolpix P520 with EVF. The Electronic viewfinder has entirely satisfied me. The tiny screen makes easy composition in all lighting conditions and also shows extra information. Where lighting allows, the big screen with swivel is handy for holding the camera over my head to get over a fence, commonplace in my Wikiphotography. Pixels? All my pix are for computer screens, which only show a million or two anyway, so the 18 Mpx is overkill. What disappoints me is the difficult holding and operating with one hand while bicycling, but not all photographers work that way. Shop for a tool that will work well your way. If you work different ways, buy different ones. Cameras, bicycles, wrenches, whatever. If you're new, you don't yet know how you'll work, so you're sure to buy wrong tools. No worry; just don't overspend on your early mistakes. The only camera part that consistently ruins my pictures is the part under my helmet, and that's not so easily replaced. Jim.henderson (talk) 19:44, 9 September 2014 (UTC)[reply]
  • Thanks for the responses, folks. Steve: Re digital zoom, yeah I know, I rarely use it. Only for distant objects when I otherwise would have cropped and enlarged the image, but without the magnification in-camera I'm not even sure if the subject is in the picture. Jim: Good point about the part under the helmet! --65.94.51.64 (talk) 04:22, 10 September 2014 (UTC)[reply]

More hints, relevant to some kinds of photography: Wikipedia:Photograph your hometown Jim.henderson (talk) 05:58, 10 September 2014 (UTC)[reply]

Ah, Real Photography (so capitalized). But real photography of what? If of individual soccer players (for example), then yes a zoom lens would be very helpful. But you may have noticed that other genres of real photography were doing pretty well in the 1970s and earlier (think of Henri Cartier-Bresson etc etc) and not only did the photographers not use zoom lenses but very often they used a single focal length (usually either 35mm or 50mm) all day. I've never once encountered somebody saying (other than as a joke) that such-and-such a photo by Cartier-Bresson, Capa, Doisneau, Model, Seymour, Ronis, Frank, Erwitt, Leiter, Levitt, etc would have been good if only the edge/corner resolution/contrast had been as high as it would be today with aspherical lenses, etc. If you want a very versatile, "high spec" camera then it will have to be at least moderately expensive and large. But probably you don't need such a camera. (Most photographers whose work is interesting do not.) Decide what you want to do with a camera and then get a camera that will do it. And when you do this, pay more attention to ergonomics etc than to numbers of megapixels. -- Hoary (talk) 13:26, 13 September 2014 (UTC)[reply]