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blinking8s
2nd of June 2004 (Wed), 10:06
in http://www.karinabednorz.de/ (awesome work) click Beatrice Heydiri and both the images in the 3rd row have unique background look to them. I was wondering with what or how this is acheived.

Thanks
-Blinks
PacAce
2nd of June 2004 (Wed), 11:07
in http://www.karinabednorz.de/ (awesome work) click Beatrice Heydiri and both the images in the 3rd row have unique background look to them. I was wondering with what or how this is acheived.

Thanks
-Blinks

That's what's referred to as bokeh and it is a characteristic of lenses that is influenced heavily by the aperture geometry used in the lens as well as the size of the aperture used for the photo. Usually, the more leaves (segments) used in the aperature, the rounder and hence more pleasing the bokeh produced.
stopbath
2nd of June 2004 (Wed), 12:04
The octagonal circles are from light sources or small bright reflections that are quite out of focus.

This effect is peculiar when using a reflex lenses as the reflections come out as donuts.
blinking8s
2nd of June 2004 (Wed), 13:52
ok, that makes sense...thanks. So its a specific type of lense that does this?
stopbath
2nd of June 2004 (Wed), 14:27
To a certain degree, the choice of lens will affect the circles, but almost any lens can do it. You need a lens that can attain a shallow depth of field, that's all (so that the round dots can get larger due to them being out of focus....)
Andy_T
3rd of June 2004 (Thu), 09:01
The shape and quality of the bokeh are influenced by the lens.

Generally, Bokeh is achieved by using a large aperture (e.g. f/2.8) and a long focal length, so that the DOF (depth of field = part of the image that is in focus) is very small.

If you used f/16, e.g., then everything (including the background) would be in focus ... but that's not the effect the photographt wanted to achieve.

Unfortunately, it is not possible to produce this kind of bokeh on digicams with small sensors, because the DOF there is much larger because of the smaller sensor. (so f/2.0 on the G3 would give the same picture as as f/8 on the 10D).

Read up on these links:

http://www.kenrockwell.com/tech/bokeh.htm (technical, no pictures :roll: )
http://www.luminous-landscape.com/essays/bokeh.shtml (technical, some pictures :? )
http://www.luminous-landscape.com/columns/sm-04-04-04.shtml (pictures :lol: )

Best regards,
Andy