What is all the fuss about bokeh? If you have never heard of bokeh don't stay up late reading about it. In a nutshell, different lenses produce different results depending on a number of factors. Bokeh is the word used to describe the quality of the out of focus area of the picture.

Th epolygonal shape of the aperture contributes to the bokeh. Lenses that have curved aperture blades or more blades to give teh aperture more of a circular feel than the angled sides of most lenses. 

So, why do you care about what is out of focus? Most people don't. In fact, lenses today are all computer designed. We have seen a lot of improvemnets in lenses over the past 20 years. so much so that minute differences are used to differentiate one lens from another. Don't get me wrong, there are some bad lenses out there. But when so many lenses are great, what makes one lens different than the next? Stuff like bokeh.

The old lens designers must be laughing from lens heaven watching us compare one out of focus area to the next. Yes, there is bokeh that is more pleasing in some shots than others but aren't we missing the forest for the trees when we start looking at the out of focus areas instead of the main, sharp, subject matter?