Dan Wallach, Rice University <firstname.lastname@example.org>
Original version: November 2009
Updated: November 2011
Over the past several years, several friends of mine have mentioned that they were considering "moving up" to a D-SLR camera and asked me for advice. I've been what you might term a "serious amateur" photographer since high school, when I was the head photographer for the school yearbook and newspaper. (It was a non-trivial issue for me to decide whether to make my career in photography or in computers.)
That said, let me make some assumptions about you, the reader of this document. I'm assuming that your world of experience with photography goes no farther than having a "compact point-and-shoot" digital camera (or maybe just a smartphone). I'm assuming you've never seriously shot or developed film, you have no idea what an f-stop or shutter speed is, and that your main complaint with your pocket camera are that your pictures aren't coming out "as good" as what you imagine you could do if only you had a better camera. If you, the reader, are in fact already the owner of a bag full of camera lenses, and you can have an illuminated argument about Tri-X versus T-Max, then this document is very much not for you.
Okay, that said, let's talk about digital cameras. You're probably going to think this section is full of techno mumbo jumbo and skip ahead to the next section. Fine, but come back here when you get confused. If you walk into a camera shop and you're not vaguely conversant in this stuff, they'll eat you alive.
Fundamentally, a digital camera is three things: a lens (either fixed or replaceable), a sensor (the thing that collects the light from the lens), and a pile of electronics (for focusing the lens, saving the images, and managing all the settings). When we talk about the specs for these things and want to compare them across cameras, there are a handful of geeky numbers worth bringing up. Every lens is rated in terms of its minimum and maximum focal length (i.e., how far it can zoom), how much light it can capture (i.e., its widest aperture or f-stop value), and a host of other features (minimum focus distance, for macro shots; weight; weather sealing; etc.). The numbers you're most likely to see are the focal length, typically listed in millimeters and often in "35mm equivalent" numbers. This is a bit wonky, but you need to understand it.
Old-school film SLR cameras and most later compact cameras as well, shot film that was 35mm wide, including the sprocket holes. The standard-sized image was 24x36mm. In that world, a 50mm "standard" lens was the default lens that most people bought with their cameras. Wide-angle lenses would be more like 24mm. Sports photographers were shooting with 400mm or longer lenses. Well, in the digital world, there's nothing standard any more about the size of the film. If you make the sensor smaller than 24x36mm, then you're effectively cropping out the center portion of the picture, which makes every lens seem longer. Most D-SLRs today are advertised as having a "1.5x crop factor" or sometimes they're called "APS-C" (after a short-lived film standard that shot 18x24mm pictures). That means that what used to be a 200mm telephoto on a "full-sized" 24x36mm picture is now "equivalent" to a 300mm telephoto lens.
Let's unpack that "equivalence." When you make the sensor smaller, cropping out the center of an image, it's a lot like you just got a longer lens. It's certainly true for the angle of view. If you want to shoot something far away, this may even seem like a feature, since bigger/longer lenses are radically more expensive than smaller ones. On the other hand, if you previously had a very wide-angle lens (which, again, costs lots of money), you're now getting less of the wide-angle, that you spent your big bucks on, when you put it on a "cropped" sensor.
Nikon, Canon, and everybody else has responded to this by making "digital only" lenses, particularly in wider-angles and zooms. Nikon uses the "DX" term to label them. Canon calls theirs "EF-S". As it turns out, when the sensor is smaller, the lens can be built smaller (and cheaper) as well for the same quality. The standard "kit" lenses that comes with most D-SLRs these days is an 18-55mm zoom, "equivalent" to a 27-82mm zoom on a full-frame camera. You can buy zoom lenses in that range for full-frame cameras, but they'll be larger and heavier than the "equivalent" digital-only lens. You need to know about this because when you go to buy a lens for an SLR camera, it will be labeled with its "real" focal length but the salesperson may tell you its "equivalent" focal length. It's very important to understand what you're getting.
Okay, enough on lens focal lengths. Let's talk about lens apertures. There is a standard numbering scheme that says how much light a lens captures. This is typically reported as an f-stop number, with smaller numbers meaning more light. These numbers work logarithmically. An "f/1.4" lens captures twice as much light as an "f/2.0" lens, which is in turn twice as much as an "f/2.8" lens. Most cheap zoom lenses will be rated for "f/4.0" at the wide end and "f/5.6" on the telephoto end. So when might you want a 50mm non-zoom ("prime") lens, which can have a f/1.4 aperture, versus an 18-55mm zoom lens, which might be more like f/5.6? The difference is four "stops" or a factor of 16 times as much light (24 = 16). That has a big impact when you're shooting in low light. At a recent dinner party, I took a picture in a brightly-lit kitchen with a 1/10 sec. exposure and my lens at its widest setting, f/2.0. You can hand-hold a camera that long if you brace your elbows at your side, to prevent jiggling the camera. (It also helps if the camera has some anti-shake mechanism in the lens, but more on that later.) If the lens was only f/5.6 at its brightest, that would mean a factor of 8 less light, and the necessary exposure would have been nearly a full second. No way you can hold a camera steady that long, and even if you had it on a tripod, people move too much. You'd get blurry pictures.
There are tradeoffs, of course. There always are. When you use a wider aperture, you have less depth of field. That means that the focus has to be bang-on, with anything too close or too far away going blurry. Smaller apertures, which let in less light, have a deeper depth of field. Now, if you have a really bright lens, you can always make the decision to "stop it down" for more depth of field, but you can't take a dim lens an make it brighter. One of the things you may think you want in a new camera is the ability to have that narrow depth of field "look". It's particularly prized in portraiture. The catch is that, say you're taking a group shot of people smiling at the camera, it's damn near impossible to get everybody in focus together, all at once, when you're using a very wide aperture. And, just for more fun, wider aperture lenses have to be physically larger to catch more light. That makes them heavier and much, much more expensive.
Let's go back to smaller sensors, for a minute. Remember that whole business about "equivalent" focal lengths? Part of what's not equivalent is the depth of field. A 200mm lens, when cropped to be "equivalent" to a 300mm lens, will have more depth of field than a "real" 300mm lens would have at the same aperture. So, if you go with a smaller sensor, you're getting more depth of field out of "equivalent" lenses than you'd have on a "full frame" sensor. Most of the time, this is a feature. It means you'll be more likely to have everything in focus at once. If you're going for specific artistic results, then of course it's not always desirable.
Finally, while we're doing all this boring background, let's talk about megapixels. It seems damn near impossible to get away from this number. It's commonly used as a basis for comparing cameras. I'm here to tell you it's meaningless. I've made reasonably large blowups from my old "4 megapixel" Canon G3 camera and my much newer "12 megapixel" Nikon D700 and you'd likely never be able to tell the difference. In fact, if you have a choice of two otherwise-equivalent cameras, made around the same time, and one has fewer megapixels than the other, you want the lower megapixel number. Crazy? Not really. Each "pixel" is a small area on a chip that's sensitive to light. If you have a lower density of pixels, then that means each pixel bucket is larger, so it can capture more photons. That, in turn, ensures that your camera does a better job of seeing in the dark, also sometimes called its "high ISO" performance. One of the things you're probably wishing you could do is get better indoor shots at night. The best way to do that is to get away from using a flash, and that means you really want a camera that can see in the dark. How best to see in the dark? Two things: having a lens that brings in more light (a smaller f-stop number, i.e., a bigger aperture) and having a sensor that's more sensitive to light. These two, together, make all the difference.
I'll also point out that my old Nikon D70 (6 megapixels, APS-C sensor, circa 2004) and my newer Nikon D700 (12 megapixels, full-frame sensor, circa 2008) have roughly the same pixel density, yet the D700 is radically better than the D70 at seeing in the dark, maybe four stops better. Every year, the camera vendors have gotten better at fabricating their sensors. Unsurprisingly, the resale value of old camera bodies drops quickly.
Still don't believe me? Check out DPReview's studio comparison tool. Select four similar cameras, make sure you've got them in "raw" mode, then start looking around. Then crank up the ISO to 3200 or thereabouts. Now you'll be able to see some of the real differences between these cameras.
One feature that you should always look for in a "serious" camera is the existence of a "raw" mode. That means that your camera writes out some proprietary "raw" file that captures precisely what the sensor saw, rather than a lossy JPEG image. The biggest benefit of this is that you have more latitude to clean up a picture after you've shot it, assuming you've got good software. I use Adobe Lightroom. Others like Apple Aperture or Bibble Labs' Bibble. All of these tools give you the ability to brighten up an image, tweak the color balance, or make a variety of other adjustments that are harder to do once a picture has been converted to a JPEG. And you can always ditch one tool for another. (You can see a list of cameras that Adobe supports. They update this all the time.)
Color balance, in particular, is worth spending a paragraph discussing. Look around you at night and notice how different kinds of light bulbs or fluorescent tubes or whatever else, have different color casts to them. Some are more yellowish. Some are more greenish. The human brain does a fantastic job of letting you ignore this, but cameras aren't that smart. The camera has to guess what the lighting is and correct for it when making a JPEG. If it gets it wrong, then the picture comes out funny. When you shoot raw, you can dial in a specific color temperature in the software and just like that, all of the hundred pictures you took at the party all look correct. (If you want to be cool, get yourself a white-balance reference card, like the WhiBal, and take a picture of it; then you just select it in software, saying "make that be white" and everything else snaps into place. You then apply that same color balance correction to all the other pictures you took at the same time.) Every D-SLR camera has a raw mode, as do many of the more expensive compact cameras. You should only consider cameras that have a raw mode.
I own two cameras: a Nikon D700 (big, heavy, built like a tank, full frame sensor, exceptionally good high-ISO performance, and did I mention that it's big and heavy?) and a Panasonic DMC-LX5 (small enough that it will fit into a baggy pocket, with an exceptionally bright wide-angle lens). For my big SLR, I own a number of big, heavy lenses. The results are beautiful, but the camera is sufficiently heavy that it stays home most of the time. For my compact camera, the LX5's lens is 24-90mm "equivalent", which is notably wide on the wide-side. Also, the maximum aperture on the lens is f/2.0, which is a full stop brighter than my very pricey Nikon 24-70mm zoom lens, which is basically standard kit for any professional photojournalist. Yes, the $370 LX5's built-in lens is superior in many respects to an "equivalent" $1800 pro SLR lens.
If you've already got a nice compact camera, you may feel that there's no point in upgrading to a better one when you can "go straight" to a D-SLR. Resist that kind of thinking. A Panasonic LX5 or something else along those lines costs maybe $400. To get a D-SLR anywhere near that price point, you're getting some serious cost reduction. You may not be terribly pleased with the outcome. In short, the only reason to get a D-SLR is if there's some awesome lens that you need to do what you want to do. If you want a fisheye lens, you need a D-SLR. If you want to shoot sports with a long telephoto, you need a D-SLR (the "super-zoom" compact cameras aren't anywhere near the same ballpark). If you want to shoot a beautiful landscape when you're hiking... maybe not. Maybe you just need a compact camera with a wider-angle lens. (This is all mostly true as well for the mirrorless interchangeable lens compact cameras, but the lens selection is more restrictive, and the autofocus performance isn't going to be nearly as good.)
Once you buy into a D-SLR, you need to understand that you're buying into a system. Generally speaking, lenses will last you forever, while you'll probably be wanting to replace your camera body every few years because the newest ones are better/faster/stronger in some fashion. As such, you should pick a system that has lenses that you want to invest in, while you understand that the camera bodies depreciate quickly. For most of you, getting a D-SLR means getting Nikon or Canon. You may be tempted to get cheaper off-brand lenses, but that's missing the point. Nikon and Canon make really great lenses and that's why you buy their camera bodies. There are a handful of lenses from third party vendors for which there aren't direct equivalents from Nikon or Canon, but if you're in the market for those, then you're not in the target audience for this document. Also, by the way, there's a whole camera gear rental market out there. Is your kid playing in the soccer playoffs? You can drop $100 or whatever and rent yourself a $5000 professional telephoto lens for the weekend. You can rent Nikon and Canon easily, often from local sources. Other brands? Online yes, but probably not locally.
The middle-ground between small cameras and D-SLRs is mostly populated by a variety of new mirrorless interchangeable-lens cameras, available from Panasonic, Olympus, Sony, Samsung, and Nikon. These cameras have the notable property that they do away with the single-lens-reflex part of the SLR camera. No more mirror box. No mirror flapping up and down. No tiny little viewfinder to stare through. These cameras look and feel a lot like a normal point-and-shoot except that you can replace the lenses. For many people "stepping up" from a compact camera, these cameras are a compelling alternative. You'll have the raw mode, the manual adjustments if you want them, and you can buy specialized lenses yet still have something light enough that you won't feel crazy to haul it around with you. Still, don't do it unless you're actually planning to buy a selection of lenses. Otherwise, why bother?
Consider this: say you want to take "macro" pictures of flowers or food dishes, or whatever else. Believe it or not, my much smaller-sensor Panasonic LX5 kills all the other options. You can take staggeringly close-up pictures, hand-held, and they'll look fantastic. This is because it's got a smaller sensor (thus more depth of field), and a lens that supports staggeringly close-up shots. On my big Nikon, I'd have to switch to my dedicated macro lens, which I usually don't carry around with me because it's more weight. And to get more depth of field, there just isn't enough natural light so I'd have to get a fancy macro flash kit. You'd never just carry that much gear around with you "just in case," which means it either stays in the back of the car, where it can get stolen, or at home, where it doesn't do you a whole lot of good.
I told you this wasn't easy. If you're just looking for a step up from your existing compact camera, the default choice for you should be a pocketable (for sufficiently large pockets) compact camera with a raw mode. You might consider:
In the not-quite-pocketable category:
But wait, there's more! Check out these fixed-focal-length fixed-lens "premium" cameras:
And, finally, the interchangeable-lens, compact, mirrorless cameras:
(Gosh, where's Olympus in these lists? They're having some pretty serious financial difficulties right now. You don't want to buy a camera from a company that's showing signs of being in deep trouble.)
Compact cameras: Which is "best" depends an awful lot on what you want to do, how much money you want to spend, and how much size and weight you're willing to tolerate. Let's say you want something truly pocketable and minimum weight trumps everything else. Get the Canon S100. End of discussion. But there are all kinds of features you leave on the table. The Panasonic LX5 does better macro and wider wide-angle, and gets sharper results. But it's too big to fit in your jeans pocket. (I keep mine in a small case with a strap that I can throw over my shoulder. Works for me.)
Superzooms: If you're willing to put up with more carry weight, you can get yourself a "superzoom" camera, or something like a Canon G12 or Nikon P7100. Why would you want this particular upgrade? You get more reach from your lens. But otherwise, it seems like mostly a lot of downsides. The Canon S100 has a better lens than the G12 (at least within its more limited zoom range). Also, many of the superzooms have a connection for an external flash. That might be interesting for some of you, but when you're talking about buying lots of accessories, you really should be looking at the interchangeable lens cameras.
Premiums: The "premium" category is interesting. The Fuji X100, in particular, has gotten a lot of enthusiastic attention from afficionados. It's got a great lens, and the price isn't insane like the Leica, but it doesn't zoom at all. Odds are, if you want to buy something in this category, you've probably already got a bunch of other cameras and are looking for a new toy. I wouldn't recommend one of these as your solo camera.
Mirrorless/interchangeable lens: Lastly, we get to the interchangeable/mirrorless category. Nikon is blasting the airwaves with advertisements for its new 1-series cameras. The other ones are also quite attractive. Why might you want one? Exactly one reason: you want the flexibility that comes with having multiple, specializes lenses, but you don't want to deal with the size and weight of a full-blown D-SLR kit. If you anticipate buying the "kit" lens and never changing it, then you're pretty much wasting your money on one of these cameras.
So what kind of specialization are we talking about here, anyway? The most variety is available for the Panasonic cameras because they support the "Micro 4/3" standard, which has been around longer than any of the alternative formats. This means you can buy lenses from Olympus and some other third parties as well that will work great on the Panasonic (example: check out this 25mm f/0.95 Voigtlander Nokton for Micro 4/3: lots of fun for available light photography at night).
According to B&H's web site, there are 37 Micro 4/3 lenses available, versus 5 lenses for the Nikon 1-series, 4 for the Pentax Q, 9 for Samsung NX, and 10 for Sony NEX E-mount. Of course, you will never own that many lenses, but variety means that when you want something specialized, like that Voigtlander Nokton, it's there for you to buy or rent.
So am I endorsing the Panasonic mirrorless cameras above all the others? Not necessarily. You can purchase all kinds of adapters. For example, Nikon sells an adapter to connect a standard F-mount lens to the 1-series camera. You can also buy adapters to connect Nikon F-mount lenses to Micro 4/3, but you can have some confidence that the autofocus will work when you've got a Nikon-branded adapter on a Nikon-branded camera. (Even then, autofocus will only work with recent G-series (AF-S) lenses; older D-series (AF-D) lenses won't autofocus with the 1-series adapter.) Otherwise, you're in manual focus territory.
Are these cameras all the same? Not even close. The Pentax Q, for example, is incredibly small and light. The camera itself is still pricey, but you can buy some relatively cheap "toy" lenses (if $100 is your idea of "toy" money) that aren't available on other cameras. The Samsung NX200, for contrast, has amazing specs: 20 megapixels, 7 frames per second shooting, etc. My much more expensive Nikon D700 is "only" 12 megapixels and 5 frames per second. But should you really let that drive your decision? I wouldn't be surprised if the Pentax has much better low-light performance than the Samsung, which is more likely to matter to you than having even more pixels.
Ultimately, you should go play with these in person. What matters is how the camera feels in your hand and whether you can make heads or tails of the interface on the back. Nikon, for example, takes great pride in how they've rethought how the 1-series cameras work, including such things as an autofocus system that can track moving objects at 10 frames per second. Sure, but will it work for you? The online reviews can tell you which camera focuses faster or has a better sensor in low light, but they can't tell you which one you'll find puzzling or pleasant. Also, check whether there's a built-in flash. These can be quite handy, but many of the mirrorless cameras require an external flash.
If you do decide to go with a mirrorless compact, then you should probably start with the kit lens that comes with the camera and also go buy one of the "pancake" lenses that are available for each of these cameras. They're smaller and brighter.
D-SLR cameras: If you want a much wider selection of lenses and accessories, or if you want the absolute highest quality sensors and autofocus systems, and you're willing to deal with the additional size and weight, then it's a traditional single lens reflex camera, with the flippy mirror inside, that you're going to want. Curiously, you'll spend about the same money, maybe even less, to get a D-SLR than an otherwise-equivalent mirrorless compact. (If weight is a concern, you might also want a pocketable camera, as discussed above. There's no rule that says you're only allowed to have one camera.) In this category, there's Nikon, Canon, and everybody else. I'm going to focus my attention on Nikon and Canon, since they're the two dominant players.
Nikon's two bottom-end cameras are the D3100 and D5100. Canon offers the Rebel T3 / EOS 1100D and the Rebel T3i / EOS 600D. Generally, the newer cameras outperform previous years' much more expensive camera bodies, at least in terms of HD video capture and megapixel rate. Whichever you get, stay away from the cheapo 18-55mm kit lenses. For Nikon, get the excellent AF-S 16-85mm VR DX. For Canon, get the excellent EF-S 17-85mm IS. For either camera, also go out and get a 50mm f/1.4 or f/1.8. (For the Nikon, you'll have to make sure you get the newer "AF-S" models which will work on your camera, versus the older AF-D ones which won't.) You're getting: One camera body, one flexible zoom lens, and one awesome bright prime lens, particularly good for portraits with shallow depth of field.
You may be tempted to buy one of the longer zooms like the Nikon 18-200 VR. Don't do it. If and when you need longer reach, spend the mucho extra bucks on a brighter lens like the 70-200 f/2.8 (available from both Nikon and Canon; for even longer reach, you can buy a "1.4x magnifier" which clips onto the back of the lens). If you've got extra cash burning a hole in your pocket, you might consider various specialty lenses, like a macro (close-up) lens.
But wait, you're not done. If you go with the SLR, make sure you buy clear filters to put in front of your lens. These are sometimes called "UV" or "Haze" filters. You can get cheap, no-name ones, or you can spend bigger bucks and get B+W or Canon/Nikon-branded filters. You should pony up for the good stuff. The purpose of these filters is that you mount them once and then forget about them. If something hits or damages them, you buy a new one and replace it. The filter takes the hit so your expensive lens stays pristine. If dirt gets on it, you wipe it off the filter, so you don't scratch your expensive lens. Similarly, one of the reasons you bought the SLR was so that you'd have all the other system accessories, so consider also getting a nice flash. You'll find they reach much farther than the built-in flash, and they recharge faster as well. For a Canon camera, you want a Canon-branded flash, and likewise for Nikon, get a Nikon-branded flash. The flash and the camera will work closely together (the autofocus system tells the flash how far away your subject is, so it can adjust the flash power output). Perhaps most important, get yourself a decent camera bag. While you can buy camera gear online, often for radically better prices than the neighborhood camera store, you should buy your camera bag in person. Take your gear with you and try each bag, one by one, to see how everything fits.
Where / how to buy: I've bought most of my gear from B&H Photo. Their prices are never the absolute cheapest, but they're always very, very close. Also, if B&H says it's in stock, it actually is. I've had surprises from other vendors. If B&H says it's backordered, they do a huge volume. You can be confident your gear will show up shortly after they get it in stock. I've also done well from Amazon.com, but make sure you're actually getting your gear directly from Amazon rather than some third-party affiliate.
New or used? You may also be able to get good deals on older versions of these cameras, particularly in the pocket compact category, like the Panasonic LX3 or Canon S90/S95. If it's new-old-stock, then go for it. The only serious feature you're giving up is HD video. (Any compact camera built in the past few years will, at a minimum, have standard-def video.) If you're looking at a used camera, then make sure you're buying in person or from somebody you trust. A scratched lens seriously reduces the value of the camera, a dead battery replacement might cost you a surprising amount, and of course, cameras at this price point aren't exactly built to last. (Top tip: when a camera first comes out, they charge a premium. The Panasonic LX5 was $500 when it first shipped in 2010. It's $370 in 2011 and it's still a great camera. If you want to save yourself some money, buy last year's hot camera, not this year's.)
This one is simple. Survey your friends. See who's got gear you might want to borrow. If you've got Nikon friends, then buy Nikon. If you've got Canon friends, then buy Canon. You should go and seriously play with the cameras, for weeks at a time, before you buy. Borrow the gear and shoot with it to get to know it well. If that's not feasible for you, then consider renting it from a place like borrowlenses.com or lensrentals.com. As a last resort, at a minimum, you need to monkey around in a camera store and make a snap judgment. Canon gear is often a tiny bit cheaper, but don't let that make the decision. Nikon gear often feels slightly better in the hand, particularly if you've got larger hands. If you're following my advice, you won't go wrong either way. I'm recommending you buy higher quality lenses, which will retain their resale value, and that you buy cheaper bodies, which will depreciate so rapidly that their resale value is meaningless.
More expensive camera bodies have features that you don't necessarily even know if you'll ever use. Will you want to shoot eight frames per second? Maybe three is plenty for your needs. Will you need more megapixels? As I argued above, you might well do better with less. If you follow the advice above, you will end up buying yourself two lenses on day one: an uprated all-purpose zoom lens, and a 50mm prime lens (which will be "equivalent" to a 75mm lens, which turns out to be a great length for doing portraits). You could then start buying all kinds of accessories. You could buy a nice tripod (advice: save money on the tripod and spend it on a good ball-head like a Really Right Stuff BH-40 LR and a matching L-bracket for your camera). You could buy more than one flash and start doing remote lighting (both Nikon and Canon support off-camera flashes; either is something of a pain to set up, but you can do things that would never be possible with an on-camera flash or with natural lighting). You could buy more specialized lenses, such as super-wideangles, fisheyes, telephotos, or really fast prime lenses that might overlap with your existing zoom lens.
My advice: you should spend four years (yes, years) or more learning your way around one of the cheaper bodies, picking up accessories as you go. At the end of all that, then you'll be ready to consider the benefits of a more expensive body. And borrow one from somebody else before you spend the money.
You've bought this thing, now make it work for you. You need to develop two very different skill sets at the same time. First, you have to learn to "see." Sounds dorky, but you have to develop something in the back of your brain that says "hey, that's a good picture." That part of your brain both helps you find good pictures (e.g., "climb over that fence so we can see what's on the other side") and also pays attention to help you improve any given picture (e.g., checking where the background and foreground intersect, perhaps to avoid having a telephone pole growing out of somebody's head). The other part of your brain has to learn to work your gear. Purists will say bad things about all these "automatic modes" on modern cameras (e.g., "kids and pets" mode). Those are crutches to help get you up to speed. Eventually, the artistic side of your brain will say "I want less depth of field" and the techie side of your brain will flip the camera to aperture-priority and dial in the widest aperture. Depending on the camera, this can be easy or hard.
The best way to learn how to see is to start paying attention to other photographers' work. I'm not talking about the guy down the street with the pile of gear. No, pay attention to what you see in the newspaper or National Geographic. Pay attention to the "masters" like Ansel Adams or Henri Cartier-Bresson. Go see their work when it's exhibited somewhere near you, or go visit a good library and look at books of their work. Yeah, the technology they used was quite different from how we do it today, but the ideas of what looks good are much longer lived. You can look at their work and challenge yourself. Hey I can do that! Your kids may or may not be willing test subjects, but it's a big world out there. (Here's a good challenge to get you started: go look at Lee Friedlander's use of mirrors, reflective windows, and shadows. Notice how the lines tend to flow seamlessly? Can you do that?)
You will experiment. Turn the flash on and off, day vs. night. Try bracing your camera against things or maybe borrow a tripod for some things. (Half of people's complaints of getting blurry pictures are because they simply weren't holding the camera particularly steady.) Never shoot just one picture when you could shoot five of the same thing. Big memory cards are cheap. Also, you'll experiment with your subjects. If you're shooting people, don't let them just stand against a wall, like it's a police lineup or something. You can pose shots or go for candids. One nerdy thing to start paying attention to is to configure your camera to blink the part of an image where you blew out a highlight. You might then decide to manually dial down the exposure to compensate. (With digital cameras, underexposing an image is almost always something you can fix later, but overexposed images are very difficult to fix.) You also want to get away from the "program" modes and get into aperture or shutter priority. With shutter priority, particularly if your camera has an "auto ISO" feature turned on at the same time, you can say "expose this image for 1/100 sec., no matter what" and the camera will figure out the rest. This may get you a grainy "high ISO" picture, but you'll have less blurring from camera shake. Learning how to use all the features of your camera, like this, is going to take time. If you just leave the thing in "program" mode, you'll never expand your knowledge.
Also, keep in mind that if you get one good picture out of every 100 you shoot, you should consider yourself a sterling success.
Eventually, you'll start bumping up against the limitations of your gear. If you want to shoot sports or wild animals, you'll find you want a longer lens. If you want to shoot flowers or food, you'll find you want a dedicated macro lens (or a compact camera with good macro support). If you want to shoot bands on stage, in dark clubs, you'll want see-in-the-dark camera bodies like the Nikon D700 or Canon 5D Mark II. You may even get bitten by the Leica bug, and consider shelling out even bigger bucks on an M9 with a few of their brilliantly bright lenses and their whisper-quiet shutter; you won't even be bothered that they're not autofocus. That's all down the line and you shouldn't worry about it now. In particular, don't stress about the fact that you may have "locked in" yourself with Nikon or Canon or the Micro 4/3 standard, or whatever else. The next big step up, after this, is so much more money that the cost of your old camera will be lost in the noise. You'll probably keep the old gear around as a backup, regardless.
Note: for all the people looking to "move up" to fancier cameras, keep in mind that some of the best professionals will "move down" to using oddball lenses, cheap plastic-bodied film cameras, and even cell-phone cameras. You can generate gallery-quality artwork with dirt cheap gear. If you truly learn how to "see," you can do great work with anything.
No I didn't. You're looking to buy a camera, so buy a camera based on how good it is at being a camera. If you're just trying to get video of your kids playing in the yard to send to the family, then your existing compact camera already does a fine job. Yes, the higher-end D-SLRs now have video support, some in high definition, and you may be tempted, but I'll argue you really don't want to go there. As a solo practitioner, you can become a very, very good photographer. You don't need exotic gear. You don't need assistants. Yet you can produce gallery-quality work. Video is a very different world. If you want to do professional caliber video, you're not hand-holding the camera any more. You need exceptionally good tripods. You need lighting to be consistent. You need much better microphones than the built-in ones. For action shots where the focus is changing, you may have somebody whose whole job is to keep the camera in focus while the action is happening. You see how big those Hollywood crews are? They're all there for a reason. My opinion: don't worry about video. Treat it as a cool feature, but not a deciding factor in what you buy.
I also didn't spend much time talking about anti-shake (VR in Nikon-speak, IS in Canon-speak, or Mega-OIS in Panasonic-speak). These things work pretty well, but they can only partly stabilize the camera. Anti-shake features do nothing to stop people or trees from moving. If you really want to freeze action, you need to use a fast shutter speed or a flash. If you really want to stabilize the camera, you can do better to brace it on something (e.g., a table or a wall) or to get a tripod.
Lastly, I made an assumption that you may have missed. I assumed that these "cropped" sensor standards (Nikon's 1.5x crop, Canon's 1.6x crop, etc.) will be around for the long haul. Both Nikon and Canon now offer "full frame" sensors in their more expensive bodies. Some people are worried that the cropped sensors, and the lenses dedicated to working with them, will become obsolete. Don't believe them and don't worry about it. The trick is that the silicon wafer that's sensing the light is a very expensive part. If you make it physically smaller, you also make it much cheaper to fabricate reliably. That's never going to change. So at the price point where you're shopping, this is a big part of how and why you're saving money. Also, it lets the matching lenses be physically smaller and lighter, which is great for not throwing out your back. And, at the end of the day, you're welcome to switch. I switched from the cropped-format Nikon D70 to the full-frame Nikon D700. I bought two new (expensive, heavy) lenses and kept the old stuff around for backup. No big deal.
Since many people who read this document may be interested in the freedom to tinker with their cameras, this section is for you. If you've jailbroken your iPhone, read on. If the thought of jailbreaking your iPhone scares you, skip on ahead.
As I said earlier, a camera has three parts (lens, sensor, computer). Well, the computer part is actually something of a general-purpose computer, if only you could install custom software upon it. With a variety of older Canon PowerShot models, you can, using CHDK (the Canon Hack Development Kit). The most notable feature of CHDK, from the perspective of making yourself a better photographer, is that it adds a raw mode to cameras that were designed without one. CHDK knows how to write out "DNG" raw files, a standard format that's widely understood by raw conversion programs. This is a nice feature.
CHDK-compatible cameras seem to be one or two generations behind the current shipping products from Canon. This means you can get them much cheaper than brand new cameras, but it also means you're not getting the latest and greatest lenses and sensors. On the flip side, you can truly tinker with your camera. Even if you're not interested in tinkering, you still can get many of the manual camera adjustments and features that are normally only available on more expensive cameras.
A friendly warning: remember how I said you need to develop two separate sides of your brain (the artistic ability to "see" and the technical ability to adjust your camera to satisfy your vision)? Tinkering with your camera software does very little for you to develop yourself as an artist. Don't get so caught up in the software that you loose touch with the art.
Phil Greenspun's page on digital cameras
David Pogue's comparison review of the Canon S90 and Panasonic GF1