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Old Apr 7, 2004, 8:53 AM   #21
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Originally Posted by LewTwo
The FZ10 also maintains a full 2.8 aperture over its entire zoom range (very good trick).
Anyone actualy know how it does it?
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Old Apr 7, 2004, 9:00 AM   #22
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Originally Posted by Japair
Anyone actualy know how it does it?
They simply put a large enough objective lens to provide f2.8 to that small sensor at 12X. The question is not how they provided f2.8 all the way to 12X, but why they didn't give a larger aperture at wide. It seems the camera should have been f1.8 - 2.8 or something like that.
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Old Apr 7, 2004, 9:06 AM   #23
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Originally Posted by slipe
f1.8 - 2.8 or something like that.
Not that 2.8 is anythin to complain about but i see your point
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Old Apr 7, 2004, 1:22 PM   #24
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>>>
They simply put a large enough objective lens to provide f2.8 to that small sensor at 12X. The question is not how they provided f2.8 all the way to 12X, but why they didn't give a larger aperture at wide. <<<

With a simple Lens (like a telescope) that is true, but I believe that the compound zoom lens we find on Cameras are a bit more complex (especially those that are internal focusing). I may be an idiot, but I think the max aperture actually "changes" due to the lens ellements movement relative to the internal baffles.

I tried to figure this out for a SONY F707 that does the same trick, but I gave up due to the migrains caused by over heating what little gray matter is left.
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Old Apr 8, 2004, 1:35 AM   #25
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Quote:
Originally Posted by LewTwo
With a simple Lens (like a telescope) that is true, but I believe that the compound zoom lens we find on Cameras are a bit more complex (especially those that are internal focusing). I may be an idiot, but I think the max aperture actually "changes" due to the lens ellements movement relative to the internal baffles.

I tried to figure this out for a SONY F707 that does the same trick, but I gave up due to the migrains caused by over heating what little gray matter is left.
Going from 38 to 190mm (eq) the Sony 707 goes from f2 to f2.4 max aperture with a 5X zoom. Run the ratio and the FZ10 with 12X going from 35 to 420mm should be about f1.8 to f2.8.

I donít pretend to understand the reason, but most zooms lose aperture as you zoom. The FZ10 has a large piece of glass in the front for such a small sensor to provide the f2.8 at 12X. There must be something different in the lens design that doesnít allow it to take advantage of that large lens at wider angles.
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