for taking photo with blur background.Camera set up:
-Set shooting mode to Aperture Priority.
-Set your lens to its maximum zoom.
-Set f-stop to maximum (f/5.6 in 55mm for this 18-55mm kit lens).
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| With zoom focal length 50mm, f/5.6, Auto ISO, Auto White Balance, shutter speed 1/30s |
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| Focal length 55mm, f/5.6, Auto ISO 100, Auto White Balance, flash trigered |
I like the natural look of the image, only some minor correction for adding contrast +3 and black +7 in Lightroom. Nikon D5100 Picture Control set to Standard. In wide-open aperture, the contrast decreased. It seems better to shift contrast up to +3 and shift sharpening about +6 for dim light condition and when widest aperture used.
Note:
-The more distant your subject from the background, the more the background "disappear".
-The wider the aperture, also will make the background much more blur.
-Some prime lens with large aperture, eg. Nikon 35mm 1.8, Nikon 50mm 1.8, has good reputation for good "bokeh" (the character how the background blur). See how the reflection from the bicycle on image above, the "glowing cycle" is pleased to look.
Visit my flickr here.
Visit Nikon's Digitutor for more information on how to setup your Nikon D5100
Happy shooting!