This is an EF lens, so it will fit your current body and any other eos you may buy in the future.

It is excetionally fast-focusing and optically exceptional.

It is a fixed focal length, but it is also pretty inexpensive for the quality of images. This is the lens I use for sports, even with an EOS 400D it can accurately track jetskis coming towards the camera in Ai-Servo focus mode.

The benefit of this focal length is that it forces a bit of working distance, so you get nice soft back and foregrounds with a razor sharp subject in between. Being f2.8 at max aperture the focusing become very very quick.

This is my favourite lens and I have quite a range.

For macro i cannot see past the sigma 70mm DG f2.8, this is another lens that is compatable with either full-frame or with the reduced APS-C type sensor of your eos 40D.

It’s not as expensive as the canon 100 macro, still gives full size and in every review I’ve read, out performs it or at least matches it.

Like every other macro lens the AF is pretty lethargic, but it is razor sharp and converts to an equivalent 110mm which is just about the most perfect focal length for portraiture.
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For the best lenses, I would suggest Canon’s L series lenses

More advise, get a fast lens with minimun 2.8F, this will help u in your sports photography.
Plus, I would recommend not buying a zoom lens with too much range such as 70-300…..
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Depending upon your budget, the Canon EF 70-200mm f/2.8L would be my first choice for a zoom lens. Second choice would be the Canon EF 70-300mm f/4-5.6 IS USM would be a good less expensive choice. One last choice would be a lens new to the market the Canon EF-S 18-200mm f/3.5-5.6 IS USM, it covers a range from wide to fairly long.

The top choice for sports though, would be the Canon EF 400mm f/2.8 IS USM, but that is also the most expensive of the lenses. It is also a prime lens, which has no zoom.

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