无意中看到这篇文章，觉得作者讲得还是比较实在的，补充一下就是Step 8 – How important is aperture?中还有一点就是取景器，大光圈镜头除了快还有一个优势就是取景器变亮了，看起来更好。而Step 7 – Image Stabilization，庆幸有机身防抖，这个问题不用考虑。以下是原文：

            8 Steps to Choosing Lenses for Your DSLR Camera

I don’t know about you but not long after playing with my brand new Nikon Coolpix 4500 many years ago, I was already dreaming of owning a DSLR. Then the day came…. my very own Nikon D70! Boy, was I a happy camper! Off course, I took it with the kit lens which was a Nikkor 18-70mm. I didn’t know much about lenses back then. But I had read that this lens was a good (but not great) average lens.  And I was happy with it most of the time. But….

Owning a DSLR means you’ll eventually be getting more lenses so that you can explore and develop your creativity. But which lenses to get? There are so many out there. And if you’re like me, going to a camera store is like bringing a kid into a candy store! You just want everything! You see a guy testing a Nikkor 70-200mm VR and you want it. Another person is buying a Sigma 105mm macro lens and you want that one too! But how to choose?
Here are some of the questions that I asked (and keep asking) myself before purchasing a new lens. These are very important steps so that you don’t go and impulse buy or just buy the wrong lens for your needs.
Step 1 – What do you like to shoot?
To me this is the most important question. Now, if you answered “everything”, try narrowing it down just a bit.  In my case, when I started out, I loved shooting bugs and flowers. I was often at the cottage and always had my D70 with me. But my Nikkor 18-70mm just wasn’t doing it for me. So I asked myself, “what kind of lens do I need to get great bug shots?” And after a bit of research I found out that macro lenses were perfect for my need. So I went out and purchased my second lens ever, the Sigma 105mm macro.

So? I’ll ask again. What do you like to shoot most? Is it birds? Then maybe a Canon 100-400mm IS would be best. Concerts? You’ll need a fast lens for low light situations so a 50mm f1.4 might suit your needs.

remember to ask yourself this question before every lens purchase or you might end up with glass accumulating dust at the bottom of a bag. I know, I have a few.

Step 2 – Do your research
Ok, so you figured out what type of lens is best for what you want to shoot. Great! But there are many to choose from. Which one, which one? Well, you’re probably wondering why I chose the Sigma 105mm over the Nikkor 105mm. The answer is simple. I did my research. I just typed “sigma 105mm review” in Google and then the same for the Nikkor 105mm. In a nutshell, I found out that both lenses had about the same image quality but the Sigma was $300 cheaper. And since I knew this lens wasn’t going to be used to generate income (even if I get their good side, bugs don’t sell well on stock sites  ), I went with the less expensive one.

You can find some great  lens reviews online. You can also check out DPReview and Lens-Reviews for user feedback.
Step 3 – How picky are you on image quality?
Don’t get too freaked out when you read some of the reviews out there. They tend to be very technical and sometimes, and I do stress sometimes, nitpick on the most minor details. That said, some lenses are just plain horrible. Luckily, in the lens world, most of the time you get what you pay for. Also, you have to ask yourself if this is a hobby or are you planning on making money with your photography? I know people that have bottom off the line lenses and are very happy. So go into the store and check them out. Better yet, do step 4!

Step 4 – Give it a test drive
So you’ve read the reviews and you found the one you want. Super! Before forking over the cash, why not play with it for the weekend? Most cities will have camera stores that will rent out lenses. It’s usually pretty cheap to rent a lens and I personally think it’s a great investment.  You can see the results on your computer and test it out in various situations. Something you can’t do in the store when you only have 2 minutes to play with it. Test it for what you’re actually going to use it for mostly remember step 1?). If you love shooting sports, I wouldn’t recommend shooting flowers in a vase.

Step 5 – What’s your budget?
A very important question indeed. If you’re a pro and you know that your new lens will pay itself off with your next 2 contracts, it’s a no-brainer. But if you’re an amateur, this becomes important. You need to ask yourself how much are you willing to spend for your hobby? Make yourself a yearly photo budget that is within your means. I strongly recommend not getting into debt for a hobby.

But if you really, really, really want that 70-200mm VR and you can’t afford it full price, try getting it used on Ebay. Sometimes, even your local photography store will sell used equipment. You won’t get super deals if the lenses are in good condition because lenses have a high resale value but you can save around 10-20%.

Step 6 – 3rd party lenses
Ok, some of you are purists out there and I respect that. But there are other alternatives from companies like Sigma, Tamron and Tokina. They also make lenses with either a Canon or Nikon mount. We call them 3rd party lenses. They used to be of lower quality but have improved dramatically over the last 5 years. They actually give the big boys a run for their money. I actually own 2 Sigma lenses.  If you’re on a tight hobby budget, 3rd party lenses can be great since they’re usually cheaper (sometimes more than 50%!).

Step 7 – Image Stabilization
Should you get image stabilization in your lenses? Before asking that question, what does it do? Basically, it lets you shoot at a slower speed hand-held without blur. Usually, the average photographer can shoot hand-held as slow as 1/60 sec. without blur. With image stabilization, you could, on average,  shoot as slow as 1/15 sec. without blur due to camera shake. Image stabilization is for camera shake only. It’s there to stabilize your camera not your subjects.  It’s great for low light situations.

Step 8 – How important is aperture?
I’m finishing off with this step because this might play a major role in your lens selection. As you might already know, the smaller the f-stop number, the wider the opening and the more light comes in which means you can shoot at faster speeds. Sometimes you’ll find lenses that seem the same at first glance but one is cheaper than the other and you wonder why. Check the maximum aperture. For example, you can get a 50mm f1.8 and a 50mm f1.4. The first one is $135.00 and the second is $500.00. Big price difference but if you’re shooting in low light all the time and you’re making money with your images than it might be worth it.

Final thoughts
One thing that I keep suggesting to fellow photographers looking to buy a new lens is to look at lenses like an investment. Camera technology advances at a neck breaking speed so camera bodies change fast and loose value. Lenses, on the other hand, don’t. That’s why lenses retain their resell value. You camera bodies will change over the years but your lenses won’t so get good glass right away. Even if you need to wait an extra few months to save up, you won’t regret it. Working with good equipment makes for a pleasurable experience and therefore better photos!  

http://yanikphotoschool_com/tutorials/7-steps-to-choosing-lenses-for-your-dslr-camera/

[2009-10-20 13:43 补充如下]

略略复述一下大概意思。
第一步，确定要想要拍什么。这是最重要的。
第二步，去研究一下想要买的镜头。网上有很多相关的资料。
第三步，确定你需要多好的画质，你对画质的要求有多挑剔。
第四步，取得镜头亲身试用。试用过才知道是否真的合适。
第五步，你的预算有多少。这实际上是一个非常重要的问题，如果只是业余爱好，没必要为此而负债。可以尝试二手。
第六步，考虑副厂镜头。如果你是资金紧张的爱好者，副厂镜头也许是很好的选择。
第七步，防抖技术。光学防抖很重要也很有用。这个和Canon和Nikon用户有关。对于配有机身防抖技术的索尼来说可以不用考虑。
第八步，大光圈有多重要。大光圈镜头可以在光线昏暗的情况下保持较高的快门速度。光圈相差不大的镜头（例如50mm的F1.4和F.8镜头）价格相差却很大。如果你真的需要经常在弱光下拍摄，那付更多的钱买大一点的光圈是值得的。
最后。镜头淘汰的速度远不如机身那么快，所以镜头较机身保值。所以，值得存钱买更好的镜头，你不会后悔的。用更好的镜头会有更好的使用感受，也更容易拍出好照片。

to 後面要用現在式
讀書時如是說,不過我英文也不好,呵呵

从语法上，这不是普通的“错误”。
如果把choosing lenses改成success，那么它就是8 steps to success，成功的8个步骤。
现在是8 Steps to Choosing Lenses，那么就是选择镜头的8个步骤的意思。

PS.正文没看

看完的感觉像做了篇英语阅读理解……还居然看懂了……
嗯，已经几个月没看过英语了……不容易……~

实在!
不过貌似对国内玩器材为主的用户用处不大.