Just wondering why a 500mm telephoto lens from Canon, or Nikon is 10,000 USD or more? I mean that is the cost of a car (surely a far more sophisticated piece of equipment)? Who can afford that? I mean for hobby purposes anyway.
They don't sell many of them, and there isn't much competition, so they tack on a premium price...because they can. If you want a car analogy, consider it a "luxury model".
[QUOTE=bkrownd;951248]If you want a car analogy, consider it a "luxury model".[/QUOTE]
Not even close. If you want a car analogy, consider it an aircraft, a prime mover, or a Formula One racer. We are not talking about pointless luxury here, we are talking about doing a very difficult job superbly well. A quality bird photography lens gathers much more light, focuses it much more accurately, and requires a lot more material than an everyday lens.
A 500 or 600 f/4 lens spends its entire working life doing a task that is beyond the worst-case ability of everyday lenses. It is operating right at the limit of the possible, flirting with the edges of the laws of physics, and the manufacturers spare no effort in its engineering.
Any lens in the 400/2.8, 500/4, 600/4 or 800/5.6 class will be very big, very heavy and very expensive. It has to be, just to do what it has to do. It needs incredibly precise engineering, and very large, expensive optical materials. You could make a cheaper one, but not if you want it to be any good, and if your lens isn't any good no-one will buy it.
If you don't want to save up for a really good lens, then you need to sacrifice something. You can give up picture quality and get something like a mirror lens or one of those $300 "bargains", you can give up reach and get an affordable 400mm f/5.6 like the Canon 400.5.6L, or you can give up light-gathering ability and get an f/6.3 500mm lens like the Sigma 50-500. The choice is yours. But if you want to do the near-impossible - take sharp pictures of small, fast-moving, often poorly-lit wild creatures - then you have to get tools capable of doing the job. There are no magic short-cuts.
But look, the simplest way to work this stuff out is to find out for yourself. Buy a cheap lens. Take pictures with it. Either you will be happy with the pictures, in which case everyone is happy, or you won't, in which case you can throw it away, write the cost of against experience, and replace it with a quality tool.
I am a firm believer in buying the best quality equipment on the market. Sure, it costs more than I can afford, but then there can be only one explanation if my shots are not as good as I want them to be: my own skill. This makes like simple, and puts the responsibility squarely where it belongs: on the photographer.