tsdh said:That's right. Therefore if somebody want to get bokeh in his/her photo, he/she must create a photo with some blur portion. So he/she must know how to create a blur background, or in other word; must understand what DOF is.
The next step:
Blur background will not always produce bokeh (blur is not the same as bokeh). So how to create bokeh? by including a high contrast dot in that blur portion.
Bokeh is actually a high-contrast dot (or a small area) which is greatly out of focus, thus it become a circle (if you want to understand this phenomenon, please read any article about "Circle of Confusion").
Some lenses produce a nice bokeh, some others not. The shape of bokeh will be determined by 2 factors: aperture blade, and the amount of spherical-aberration correction in the lens. Over-corrected lens, tend to come with ring-shaped bokeh.
Thank you...tsdh said:Diaphragm blades is just half of the story. It only determines the outer shape of bokeh (whether it is pentagonal or hexagonal or round).
But the most important factor, is the lens design.
A ring-shaped bokeh will still look bad even if its shape is fully round. And a lens with that kind of bokeh, can not produce a smooth background blur with blending colors, although it is usually able to produce very sharp image.
This is one of the properties which is emphasized on a "portrait lens". (bokeh will be mostly important on portraiture and macro photography).
Your explanation of Bokeh very concise. Now, when someone says to me this lens has creamy Bokeh I have a better understanding of what it means, it is the smooth rounded high contrast blurr of the background.
I have a question, if the lens produce a hexagonal shape Bokeh, will adding a soft focus filter makes the Bokeh appear nicer? just looking at Bokeh for this instance.
Trying to find out what can I do to produce the optimum of the gear I had without forking out too much money, i.e.; looking for available options... since Bokeh is very important for portraiture.