Since this one gets asked every month or so, I'll try and give a definitive answer here.
I have an equipment problem
I'm always impressed when I see someone who takes fabulous photos who has only one camera. I realize they're focused on their art, they have a great vision, they have the tool they need, and that's it. I'm really the opposite, I'm a total equipment hog. Whenever I see a photo taken with some bit of gear that I don't have I think This is why my photos suck! Because I don't have a (softbox, beauty dish, 300 f2.8, wireless flash trigger, camera that shoots 7fps, etc) and I go out and buy one and maybe my pictures get a little better but then I'm always confused as to what to use.
Whatever it is, make sure it's digital
I went digital in 2000 when I got a Nikon Coolpix 950 point and shoot I got it because it was the only camera I could find (apart from the Nikon D1 which came out the same time but cost $5,000) that had a flash sync built in. For a while it was the only camera I really used much because digital was so convenient.
I shot this photo of Carfax Abbey with it:
Clickenzee to Embiggen
This image is a 729k jpeg taken on a 2 megapixel camera and it remains one of the best band photos I've ever done. I have a 40x50 inch enlargement of it hanging in my kitchen and nobody ever says "This looks a bit funky, did you take it with a two megapixel camera or something?" -- it's got a good idea behind it and it's relatively well pulled off.... But there were downsides to the 950 -- lousy battery life, no interchangeable lenses, etc. etc. So eventually I bought a Nikon d100 dSLR, and then upgraded that for a d200, and that for a d300, and the d300 got stolen on a train in 2008 and I upgraded to a d700 which is what I use mostly now.
Why choose Nikon?
Nikon and Canon and Pentax and Sony and Minolta all make cameras that are technically similar and for the most part as good as one another. Nikon and Canon hog the bulk of the professional dSLR market however which means that if you're in a room full of photographers and you get shot in the lens by a bank robber and the lens explodes on the floor and a robot duck runs off with the pieces of it, chances are, if you have a Nikon or Canon, one of the other photographers in the room has a spare lens you can borrow. (This is true as well for battery chargers which is probably more likely but not as exciting.) It also means that there are more Nikon and Canon lenses on the used market. Which, as far as I can tell, gives a practical advantage to owning one of those. If you're in the photo-pit at the 2012 Democratic Convention or a Lady Gaga show looking for a batter charger for a Sony Alpha you're probably on your own.
On top of that, Nikon has never (not really but practically) changed their lens mount. Which means that every single lens they've made from the 1960's until today (with a few exceptions) will fit on the Nikon dSLR you buy today. Which means you can put a manual focus 300mm f2.8 lens made in 1985 on your Nikon d700 and pay $700 for it instead of $3000 for the latest autofocus model. That's what's kept me in the Nikon camp. Your mileage may vary.
OH HOW I WANT A LEICA (but not for any of the right reasons)
Although ever since I picked up a Leica M6 I never really wanted to use another camera. Oh it's beautiful. It's like driving to work in a Formula 1 race car for a year and then you lose it and someone gives you a 1984 AMC Gremlin. You're deflated, even though the gremlin has seats for your friends, a trunk to put luggage in, it gets better gas mileage, has windshield wipers, an 8 track player and a heater -- things just aren't the same. Don't ever pick up a Leica. It's like tasting the free drugs.
Anyway, everybody who's ever owned a Leica wants nothing more than a digital Leica because, seriously, who wants to muck about with film anymore? It costs a lot, it's time consuming, and by the time you get your negatives developed, the magazine's already out with someone elses photo on the cover. So they're all like coked out junkies hitting the refresh button on dpreview.com every 20 seconds waiting for the headlines that says "AWESOME DIGITAL LEICA ANNNOUNCED!" drinking coffee and twitching like nerve-gassed wasps trying to stay awake so they don't miss it when it happens.
Leica had a few false starts at making digital cameras, most of which looked like Kleenex boxes and were two years behind everybody elses technology (they seem to have done it now with the Leica M9, which is like $8,300 on Amazon. But in the meantime, Panasonic came out with a very Leica Like camera for about $700. This was more my speed and I bought one and I love it. It's really small which makes it more likely for me to carry around and it has interchangeable lenses. Here's a photo of me looking very happy with mine.
You want advice? Forget the camera, get the cool lenses
In all of these though the camera body is less important than the lenses. There are a couple of "Sweet Barking Cheese!" lenses that I use which Rock The World
I'd always thought that a fisheye is something you use very sparingly, it sits in the bottom of your camera bag waiting till the perfect day, but after getting one, I found that I use it all the time. Especially with software like fisheye-hemi that will un-fisheye images and make them more useful ultra-wide shots with little distortion. It's awesome for getting a whole room into a shot.
If I had to pick one lens, this would probably be it. (The cheap alternative is to use the 50 1.8 or 50 1.4) wide open it has a lovely shallow depth of field that just punches people in the face with THIS IS A PROFESSIONAL PHOTO. I shoot it wide open all the time.
This is the workhorse of photojournalism. There's probably no real news photographer who doesn't carry one with them ALL THE TIME. It's a beast, it's heavy, but it gets you a headshot from 15 feet back. It's the lens to photograph people on stage, press conferences, that sort of thing. The wide aperture makes it work well in low light, it's an awesome portrait lens. Most everything you can do with the 85 1.8 you can do with this, but it weighs 5x as much.
Another lens I use ALL THE TIME is the Sigma 12-24 it's a slow, heavy lens but it's super wide and if you're shooting interiors, you may need one. I shot almost the entire Armed America book with it.
Here's Jared Axelrod and J. R. Blackwell rockin' the 12mm.
I can take a good photo with anything!
I've also gotten a bit crazy about taking photos with my iPhone. It used to be more of a challenge, but the camera on the 4g is better than my point and shoot, so I end up using it. It's still a novelty, the idea of saying "I took this with my phone" implies "I must be pretty darn cool" I like the idea of a camera you have with you all the time, I like the challenge of doing stuff without equipment
So, that's it. Feel free to chime in with your thoughts, opinions, least and most favorites, what's worked & hasn't, and do feel free to repost this or link to it.
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