This is the biggest subject with all DSLR cameras.
Which lens for me?
Ask 20 people and you will get 20 different answers;
and all will be good answers for that person.
It is a matter of choosing what is best for you.
Knowing more about lenses never hurts.
Here are some important facts:
Whenever you see the mention of focal length for a lens on digital cameras, you can see two sets of numbers.
One is the actual focal length for that lens.
One is the 35mm film equivalent focal length.
Most people quote the 35mm equivalent number because it gives you a comparison number, so that you can compare apples to apples.
High priced DSLR cameras ($5,000 and up) have a sensor that is the same size as 35mm film.
Lower priced DSLR cameras have sensors that are smaller than 35mm film. Therefore to get the 35mm equivalent focal length you have to multiply the actual focal length by 2 (for the Olympus).
If you see a Olympus zoom lens rated as 17.5 to 45mm, that is the actual focal lengths. When you put that lens on the E500 (with a smaller sensor), you have to use the multiplier (2) to get the 35mm equivalent focal lengths.
That 17.5 to 45mm turns
into 35 to 90mm when used on the E500.
Hopefully this link will be easier to understand:
http://www.dpreview.com/learn/?/key=focal+length+multiplier
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Aperture (or f-stop) rating:
This is a rating of the amount of light a lens can collect. The smaller the number, the brighter the lens.
The Nikon 17.5 - 45mm lens is rated f3.5 to F5.6
What this means is that the maximum brightness is f3.5 and when you zoom that lens out, it is then rated at f5.6
Yep, the further you zoom, the less light it can collect. It all has to do with the mechanics of lenses and cost.
Here is a quick write-up about aperture:
http://www.dpreview.com/learn/?/key=aperture
An f-stop of f2 can collect twice the amount of light as an f-stop of f2.8.
An f-stop of f2.8 can collect twice the amount of light as an f-stop of f4
etc.
When comparing zoom lenses, the brighter the lens, the more expensive the lens.
For low light work, many people will select a 50mm non-zoom lens (native) with an f-stop of f1.8
These can be found for under $100
A zoom lens with a rating of f1.8 will be priced out of sight.......That is why they don't make them.
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My suggestion......buy a kit lens (17.5 to 45mm) to start with.
Nikon's kit lenses are excellent.
Learning the features on the E500 and that one lens will keep you busy for about 6 months.
By that time you will have discovered what future lens you would like to have.
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