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Old Dec 5, 2005, 2:37 PM   #11
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Hrmm

the way I think of magnifying devices are how they're made.

A tele lens is just a lens with a very small angle of view.... The thing is you're filling up the sensor with 5 degrees of view as opposed to something like 45 degrees. It never did anything to mess with reality.

That last part may sound akward, but let me try to explain.


For instance:
-take a tele lens that has 5 degrees of view (which looks like something in the camera format) and take another lens with 45 degrees of view (which looks like something else in the camera format). This is the default for all cameras (I'll just reuse the word, "reality"). Each time you use a different angle of view, you get a different result, but all results will remain the same on all cameras.

-magnification changes how the picture will come out... if you used a tele and have 5 degrees of view, and you see a bird's head.... That's your original picture... Now attach a close up lens that magnifies the picture by 2. You still took the picture with 5 degrees of view.... but it's no longer the same because now you only see the bird's eyes... it's different from the default picture that you would normally get on a camera... hence, you "altered reality"

My 2.5 cents
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Old Dec 5, 2005, 4:04 PM   #12
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Ahh! Thanks for sharpening my understanding, Terry and BoYFrMSpC.
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Old Dec 5, 2005, 7:08 PM   #13
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[email protected] wrote:

Quote:
Keep in mind that a telephoto lens does not "magnify" the image.

A telephoto lens simply picks out a narrower frame of reference.




Actually the 50mm/9.375mm are supposed to be equivalent due to the different sized sensors, but I know what you mean.

Magnification is all in how you look at it. (to me) magnification is a matter of how many focal lengths away you are.If all you are interested in is image size, thenthis canbe acheived in two ways,

1) move closer

2) use a longer focal length

Fewer focal lengths away, bigger image on sensor.

Of course the difference between the two is perspective, (and I discovered apparant background blurr). These are a matter of angle of view, which I'm still trying to get a handle on.

matt
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Old Dec 13, 2005, 12:54 PM   #14
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[email protected] wrote:
Quote:
Keep in mind that a telephoto lens does not "magnify" the image.

A telephoto lens simply picks out a narrower frame of reference.

For instance, a very long 600mm lens can pick out a bird sitting in a tree at several hundred yards, while ignoring everything else around the bird.

Whereas a 15mm wide angle picks up a huge wide angle vista, where you'd be lucky to pick out the bird in the tree because you'd be taking a picture of a hundred trees.

Anyways, most people don't realize what I just told you.

-- Terry
That's about the best description I've seen for telephoto.


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