Help me choosing good lense.

[asim99]

Hi,
i am going buy Canon EOS Rebel XSi (a.k.a. 450D) SLR Digital Camera. it comes with 18-55mm IS Lens . But i am considering some other lense with better zoom power ( about 10X )and good working in low light. I am neither professional nor i know too much about digital camers. i am one who wants to start learning with good camera. please tell me which one of the following is better.

1- 18-55mm IS Lens
2- Canon Normal EF 50mm f/1.8 II Autofocus Lens
3- EF-S 55-250mm f/4-5.6 IS Autofocus Lens.

The third one is littel expansive. please also comapre cost to advantage ratio.

Thanx

[SmartWombat]

The x part of the soom is the difference between wide and telephoto ends of the zoom, so you'd be looking at 35-350 or 50-500.
10x zoom is not going to work in low light, nor is it going to be great quality.

For low light you're going to need f/2.8 at least.
So of those the only one usable in low light would be the 50mm - a great lens.

I use the 24-70 f/2.8L, 70-200 f/2.8L and 50mm f/1.8 from Canon.

[asim99]

as i told earlier that i don't know much about digital camers, so please guide me. i think f/1.8 is better then f/2.8. am i right?

[EOSThree]

as i told earlier that i don't know much about digital camers, so please guide me. i think f/1.8 is better then f/2.8. am i right?

f/1.8 is a is a bigger lens opening (aperture) than f/2.8, and usually a lens with a wider maximum aperture will be a better lens. Prime lenses usually have a large aperture and the cost isn't too bad. A large aperture zoom lens usually costs many times what it's smaller aperture equivalent does. I am a landscape photographer and for me a large aperture lens offers little benefit, but the best lenses(in all areas)are usually the large aperture lenses. I have chosen to build my kit around the best zooms in the maximum f/4 range, and around mostly constant aperture zooms.

The wider apertures let more light in and allow for easier available light photography. That is changing some as modern digital cameras offer great low light performance at the rotation of a dial. Generally wide apertures will offer great benefit for indoor and motion photography allowing you to choose a shutter speed fast enough to stop the motion, while possibly avoiding the use of flash.

What you have chosen above will be a good kit to get you started and will allow you to take a lot of great photos. The lenses have some limitations, and like Wombat says, they don't offer much in the way of low light performance. But as I stated above it depends what kind of photography you intend to do. Those two lenses are close to the bottom of the line for Canon lenses. Canon's best lenses cost many times what that #3 lens does. The equivalent pro grade lens with a fast aperture will cost between $700 and $1800. Those two you picked will perform well, and will take very good photographs, they may limit your low light photography, and they may limit your action photography to only good light.

I guess for comparison's sake, I use Canon lenses: 17-40 f/4L, 50 f/1.8, 24-105 f/4L, 80-200 f/2.8L, 100-400 f/4.5-5.6L, and for sale: 300 f/4L.