Wherever there are reports about a new camera lens, this sentence is often found. What characteristic of the image is actually meant by it? And what does the diaphragm have to do with it?
We would like to address these questions today. But because "bokeh" is closely related to "depth of field," I would like to first begin with those topics on the following pages. It is true that a great deal has already been written about them elsewhere, and many may think that the topics have already been exhausted. Nevertheless I am sure that you will not be bored. I will use a rather unusual method to show how to use a little geometry to very clearly understand the most important issues of ‘depth of field’.
