Re: what lens for elan7? That is the name of the Canon autofocus mount. You can buy other brands
in the same mount, such as Tamron and Tokina (at-x not sz-x). The older
Canon FD mount lenses will not fit onto your AF Canon. Those are manual
focus.
The 3.5-4.5 is the faster and more expensive lens. Not a supremely big deal
of a difference other than one stop faster than the other. You might consider
spending more on a zoom of a constant 2.8, just for speed with ISO 100 film.
$1200 - $1500 btw, if new.
But for your film camera, make sure that whatever you buy is not in focal lengths
for digital SLRs, as the projected image circle will be too small for the frame
size of 35mm film, and you'd get black vignetting in the corners of your shots.
Those numbers represent the aperture ratings of lenses, as lenses have multi
bladed diaphrams to allow more or less light to the film, as well to allow less
or greater depth of field. The numbers show for the lens the widest aperture
capable of any given lens. Obviously, the larger_the_better meaning more
"speed", allowing all the more light through the lens to the film. As well, the
smaller the aperture is the more depth of field given, and helps with the
sharpness of the image as the rays of light that are carrying the image to the
film become much more finite.
The smaller that F-stop number is, represents a "larger widest" aperture the
lens is capable of, and more expensive.
Smaller number = more and wider glass = more speed = mo' money!
Check prices on zooms with a constant F/2.8, you'll see. I just bought an old
manual Tamron SP 70-210 constant 3.5 zoom for a great price. That's 1/2
stop slower than 2.8. But a constant same aperture at all focal lengths in a
zoom lens, from one end to the other, is the most desireable.
50mm 1.4 and 1.2 are available, and Canon has made lenses of 0.95, a-way
back in years past. That is HUGE and fast as hell.
Lenses that end in 5.6 are the cheapest and slowest. When you see f4-5.6 on
a zoom lens, you can see that the aperture value changes from wider (faster)
at the shortest focal length to a stop slower at the longer focal length. Faster
is more wide open, and slower is more closed down.
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}<)))*> Giant_Alex
cravdraa_at-yahoo_dot-com
not my site: http://www.e-sword.net/
AAvK
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