Newbie question re. sharpness
"gwperil" schreef in bericht
ups.com...
Hi,
I have what is hopefully a pretty basic question. I have a Canon 350D
with the two kit lenses:
* EF-S 18-55mm 1:3.5-5.6 II
* EF 75-300mm 1:4-5.6 III USM
As a test, I tried taking the "same" photo with each lens; that is, I
framed a still object as closely as possible with each lens and used
the same settings: Manual mode, 1/100s, f/5.6, ISO-100, Flash
(Speedlite 430EX pointed ahead), tripod. Obviously I had to move the
camera back to get the same shot with the 75-300. The only other
difference was of course the focal lengths: 45mm vs 75mm.
The picture taken with the 75-300 came out much sharper than with the
18-55. What accounts for that? I ask because, in general, I'm able to
get better looking pictures out of the 75-300.
Thanks in advance!
Both lenses are not producing very good pictures 'at the ends'.
So, don't use 18 and 55 or 75 and 300mm
Same for the aperture. Stay away from the ends.
Compare them again in the middle sections, ergo around 35mm and around
150mm, both with f8.
I think the difference will be less.
(beware that the largest apertures will become smaller when zoomin in. f5,6
will be wide-open in tele, dont't use it)
br
Aad
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