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Old 7th March 2006, 03:25   #20
sgtfuzzbubble011
 
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Join Date: Jun 2000
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noisy.
Yes, but cool.


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They would be huge and extremely expensive. To get that kind of light gathering power, the lens has to be very large in diameter. Add a zoom mechanism to that and it gets unwieldy very quickly.

As far as price, larger lenses are more expensive because, besides being larger, it is more difficult to make a larger lens with the same precision as a smaller lens.
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Because lenses have to get bigger to collect the same amount of light at increasing focal lengths. In zoom lenses, because of inefficiencies, the problem even becomes bigger.

It is pretty unusual to see lenses below F 2 that have zoom optics. To get F8 at 3500mm, this Minolta "lens" I have uses a 4 " mirror.

In optical terms, it's what they call a Schmidt camera. What I call it is a really expensive lens that is just about useless
True. It's just really annoying and irritating that it's pretty much impossible to find a lens that has exactly what I'm looking for... much less being able to afford it.

Cool pictures, though.
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