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I have Nikon D7000 and I know the basic relation of shutter speed, aperture, and iso.
All I want to know is focal length and aperture relation.
As I zoom in the camera the f/stop increases (e.g. it starts 3.5 and then to 5.6)
Some one told me that having large aperture gives more blurry background. (ie: f3.5 will give me more blur than f5.6, if I am not wrong)
However, when I zoom my lens to 140mm minimum f value available becomes 5.6 and it gives me more blurry background than f3.5 at 18mm
Why is this?