What to consider when buying a lens.

[atseeyob]

Well, this is the beginner place so what the heck to ask some basic questions. Based on the advice from this forum and other research, I am buying Canon 30D unless someone convince me not to do so. The question now is the lens and accessories that goes with it. I have seen numbers like 70-200mm which mean nothing to me. Please let me know what to buy. Also flash and memory card.

For some weird reason I have immense passion for photography and I am about to take my first class.

This forum is so great and hope to use it a lot in the future. Thanks.

 

[chrisk121]

It depends what you want to shoot. The numbers like 70-200 show the focal length of the lens or how much it zooms(http://www.usa.canon.com/app/html/EFLenses101/focal_length.html). If you still don't understand, it's kinda like the 4x zoom on point and shoot cameras, just explains a little more. for a beginner , I would recommend a standard zoom like the kit lens(18-55). Or if you have a little more money, you could get a 17-50 f/2.8 tamron or a 17-55 f/2.8 canon(expensive). The f/2.8 numbers mean how wide the lens opens up. Wider, more light gets in allowing for faster shutter speeds(http://en.wikipedia.org/wiki/Shutter_speed) and narrower depth of field(http://en.wikipedia.org/wiki/Depth-of-field). The lower the number, the wider open the lens is.

Are you getting the 30d package with the kit lens?

 

[astrostu]

I am buying Canon 30D unless someone convince me not to do so.

I don't think anyone here will try to convince you against buying a 30D (have you considered a 40D?) if you've made up your mind, but (and no offense ...) if you don't know what something like a "70-200 mm" lens means, are you sure you want to buy such an expensive camera body when you don't know much about photography? I started with a point-and-shoot and got a lot of use out of it and was able to produce many very good photos. It was only at the point where I consistently wanted to do stuff that the point-and-shoot wouldn't allow that I upgraded to the Digital Rebel (350D). And it does almost everything I want now, but I do see myself upgrading to the successor of the 5D in maybe 2 years. There's no point in spending a lot of money if your skill level won't allow you to take advantage of it.

I have seen numbers like 70-200mm which mean nothing to me.

That refers to the focal length of the lens - basically how far in front of the camera the light enters the lens. The focal length determines how much of a scene is recorded by your camera. The longer the focal length, the more narrow your field of view (not to be confused with depth of field, which is how much depth is in focus). The shorter, the wider. A good image illustrating this is shown here: http://www.thephotoforum.com/forum/showthread.php?t=89143 . A few extra mm less on the low end makes a huge difference whereas many extra mm on the high end makes a small difference since the field of view is goverened by an inverse tangent function.

Please let me know what to buy. Also flash and memory card.

You need to really sit down and figure out what you want to do and what tools you need to accomplish that. Do you want to do street photography? Then get a normal lens (50 mm). Do you want to do product photography? Then get a long lens with macro. Etc....

 

[soylentgreen]

Nothing I can really add that the other two members have not already stated. Hold out for the 40D if you are going to make that jump. Should be out by late September. Otherwise wait till than also, because price ont he 30D may drop some. The 40D is a sweet rig though. . Anyhoo, do not go lens buying crazy until you settle on what you want to shoot and the lenses that are best suited for those needs. Come back with more questions when you arrive at that point. At first, just pick-up a standard general purpose lens, shoot with it for a while, and go from there. Canon offers 3 kit lenses to start, the 17-55, 17-85 and 28-135. I like the one in the middle. Good wide angle, decent zoom. My two cents.