The out-of-focus shapes will be determined by both the blades of the
aperture and the size (and somewhat the shape) of the out-of-focus light
source. The larger the light source, the fuzzier the image of the blades.
The distribution of light in the image gives a clue to the bokeh of the
lens. The image of the aperture blades is fairly sharp, therefore the light
source is very small. My guess is they are street or area lamps in the
distance. The image of the aperture will be present regardless of the chosen
stop, but wide open, the aperture is round. Many aperture blade designs are
somewhat curved. There is slight, but very little curvature to the sides of
the heptagon suggesting that the lens is stopped down a bit. My wag (just a
wag) would be at least 2 stops from wide open. The out-of-focus image is
extremely large. This requires a large displacement of the lens between
close focus and infinity along with a big aperture and suggests a fair
telephoto lens. Fiddling around with my lenses *suggests* 135mm or larger,
perhaps larger focal length. Bokeh is probably neutral and might appear a
little harsh in normal portraits.
Just my wag...
Regards,
Bob...
Give blood. Play hockey.
From: "Collin Brendemuehl" <[EMAIL PROTECTED]>
> I'd say just the opposite. Aperture design shows up at about f11.
> I'd guess this at f16. That would account for the sharpness of
> the subject who is relatively close. That requires a lot of DOF,
> only available at a small aperture.
>
> Evaluating the focal length is more difficult. Because the background
> is a bit compressed to the subject, I'd say a 135mm lens, or at least
> 100mm. That would also account for the flash not lighting anything
> in the background.
> >From: Kelvin Ang
> >Can I refer you to the following image I came across:
> >http://www.defenselink.mil/photos/Feb1998/980119-A-6522J-503.jpg
> >
> >The dark, blur background and the 9-sided image of a
> >light source far into the background suggest that this
> >photo is taken with a very big aperture. (Please
> >correct me if I'm wrong)
> >
> >Can you suggest at what aperture and focal length that
> >photographer took the photo at? I would like to buy a
> >lens that allows me to shoot this kind of photographs.
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