IMHO, you start out with the best body that you can afford, especially if youre like me who is not planning on changing camera body any time soon (because of financial and commonsensical reasons). Get one that will give you a lot of leverage when it comes to functionality (more room for tinkering around to your imaginations content) and future-proofness (meaning one that wont go obsolete after you buy it, but Im not saying it wont). Get a kit, its cheaper and has distinct advantages to it. Something that you can work on and discover the basics and functionality of the cam. When youve mastered your kit lense, then you can start thinking of the expensive lenses. Keep your eye on what matters most right now, getting yourself great quality equiptment that you can afford which you can master the basics with. Then we can talk about post processing, and the other essential stuff. Its a half truth when they say its all about the "Indian" and not the "pana". No matter how good you are, if you equiptment cant deliver to your expectations, you will never be satisfied with it. On the other hand, if you have a pretty good set on your hand and it enhances your photography skills (especially if you have other equipments to compare it to), youll always want it by your side. Especially since art and beauty is rather relative to each one.
So with that said, here is my choice.
I start with a Nikon, definitely better optics, better build, and it being a design of Giugiaro doesnt hurt one bit.
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If youve got big hands like me, Its definitely easier to hold and the controls are very well thought of. I wont go into the tech details so much as I have found myself overwhelmed with the tech details from reading all the reviews for the past 2-3 months. But these are the essentials, I love the viewfinder of the Nikon and find it easier to compose photos especially with the built in grid. The focus on the Nikon is awesome... hasnt failed me yet. The menu system is great and easy to navigate. and one of the best feature is the little LCD screen on top of the unit that displays the info... definitely readable in bright sunlight and works well at night too... I have to keep myself from ranting and raving about the Nikon as Im just in love with my D80.
The stuff I like about the Canon 400D though is that its light... very very light. If youre going to be taking photos the whole day or trekking somewhere or in the Sinulog Mardi gras, youll love how portable this thing is. It looks very high techy... while the Nikon has its old world charm. I think its navagation buttons are better because these are 4 separate buttons, unlike the Nikon where its one "rocker" button which can be a little tedious. Ive tried using a friends 400D for a while and a Nikon D70s and both units are definitely not bad. The Canon is small enough to stuff into an overnight bag with room to spare. The Nikon is definitely hefty. I feel this is because of the construction and buid quality. You get great Canon warranty... which is available almost everywhere. Whilst the perennial problem with Nikons warranty and Columbia Photo (Nikons official service center) and the grey market units have had developments only recently.
Bottomline, the D80 is more expensive than the 400D and for the right reasons. I got the D80 and im loving it and have not regretted shelling out more for it. The D80 usually comes with the 18-135mm kit lense, while the Canon comes with the 18-55mm kit lense. I suggest you try out both cameras first, and then see which one youre comfortable with. I can also recommend to you a seller that will give you a very good price for which ever unit you decide on. I got my D80 from him and so far so good! 600+ actuations in a span of exactly 10 days. trigger happy. hehehe
I hope this helps.