I use nikon D90 with the kit lens (18-105)
and when I use manual mode and set the F stop to 3.5 (the lowest it can go) it doesn't make a difference to the focus of the background, as to when the F stop is a higher number.
what settings do i need to use so the background is more out of focus, or do i simply need to buy a 50mm lens?
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How to take pictures with blurry backgrounds on nikon d90?