Like many people, when I first started getting into photography (or more correctly, when I started getting back into photography), I was focused on the camera.
Over time, I learned that it's less about the camera and more about the lenses, or â€œglassâ€, to use the term photographers use. It's not uncommon for a photographer to get attached to their lenses and keep them for years.
After you've shot for a while, you may find that the results that you're getting aren't quite up to what you were hoping for - you'd like to get pictures that are more like the ones the pros get.
At that point, it might be a good idea to think about new glass.
The 70-200mm zoom is a great lens for shooting field sports - it has enough reach to bring players close but it goes wide enough to handle players that are close. It's relatively light and relatively cheap.
This is such a popular lens that Canon makes four different lenses:
Why did I choose those lenses? Wouldn't Canon's 100-300mm F4.5-5.6 be a much cheaper choice at $295?
It would be a cheaper choice, but it wouldn't be a satisfying choice.
The four lenses are part of Canon's â€œLâ€ line of lenses - the ones that are designed for pros. They have superior optical performance, especially at the wide apertures where you will spend most of your time. They also are faster (gather more light) than the non-L lenses, and have faster focusing systems. At least some of them are parfocal, which means that you don't have to refocus if you change the zoom.
You do pay a weight penalty. The 100-300 weighs 1.2 lbs, and the 4 lenses I list weigh 1.6, 1.7, 2.8, and 3.2 pounds. I have the third one on my list - put that on my 40D and together they weigh 4.4 pounds. I'm okay using that for a game, but I shot at a charity 5K run recently and my arms were killing me by the end.
The â€œISâ€ on some of the lenses says that the lens has Canon's excellent image stabilization built in. Stabilization reduces the shaking of the camera when you handhold a lens. I have a 24-105mm F4L IS lens, and the stabilization on that is scary good.
But it doesn't help in a lot in field sports. I'm looking to freeze the player's movement, and having a nice stable background with blurry players isn't much help.
My recommendation is that you start at the cheap (well, less expensive) end of the range, and try the 70-200mm F4L.
There are other lens makers - Tamron and Sigma come to mind - that make lenses that also cover this range. I've heard that some of them are pretty good, but I prefer to stick with the Canon L lenses, because I know what their quality is and they hold their value well. If you want to buy a non-Canon lens, I suggest you compare their review scores to those of the comparable Canon lenses.
Nikon also makes excellent lenses in this range, but frankly, the whole Nikon lens line confuses me, so you're on your own there. If anybody can give good Nikon recommendations, please feel free to add them in the comments and I'll include them here...
Unlike camera bodies - which depreciate at an alarming rate - lenses hold their value well. You can find well-cared-for examples of any of the lenses I've listed, and you might save 30% or so on a used lens. And, if it turns out that you don't like the lens, you can resell it, often at pretty much what you paid for it.
There are pros that do this regularly - they'll buy a used expensive lens, use it for a specific assignment, and then resell it.
It pays to do some research before you buy a used lens - in some cases there are multiple versions of a single lens (with different quality), and sometimes a lens will have production issues that are only fixed in later versions.
Two of my L lenses came from the buy/sell forums on FredMiranda.com. There are also some online stores that offer used lenses.
Canon's 100-400mm f4.5-5.6L IS Lens ($1680, 3 lb) is sometimes used for sports, but it's a bit slower than comparable lenses.
Most of the lenses beyond 200mm are prime (non-zoom) lenses.
There's the very popular 300mm F4 L IS ($1300, 2.6 lbs) and 300mm F2.8 L IS - ($4600, 6! lbs). Most people use a monopod for the F2.8 variant, because of the weight.
If you need longer, the 400mm F2.8 L IS ($7500, 11.7 lbs) and finally the 600mm F4.0 L IS ($8300, 11.8 lbs) are also available. Maybe little Johnny will get that basketball scholarship...
The 600mm is a bit large as well. That tiny silver thing at the back is the camera body...
A teleconverter attaches between the lens and the body and offers an extra multiple of magnification. Add a 1.4x teleconverter to your 70-200mm, and it magically becomes a 100-280mm lens. In the process, you lose some image quality, and that F4 lens becomes an F5.6 lens - you lose shutter speed and background blurriness.
Whether it's acceptable depends on whether you can afford the loss of image quality and light. Canon L lenses are good enough that the loss of image quality is often acceptable, so if you have the light it's interesting to try, especially if you have an F2.8 lens.
There are also 2x teleconverters - in these you turn the F4 lens into an F8 lens, which won't even autofocus on many camera bodies, and you lose a lot of image quality. I don't think it has much use in sports.
Before you drop $1K+ on a lens, you might want to try it out for a week. You can rent a 70-200F2.8 L for about $60 for a week, a small price to find out if the lens is worth it for you.
It would be nice if all lenses were perfect from the factory, but unfortunately that isn't always true. In some lenses the normal manufacturing tolerances line up to produce great results,and in some they go the other way and result in average results. In some cases, the manufacturer can service an average lens and turn it into sharp lens. If you think your lens isn't performing the way it should, you might want to do this, preferably while the lens is under warranty (one disadvantage of buying used).