There is still a lot of confusion out there about Bokeh.
What is it (really), how does it effect our photography, how or why do you apply it and where do you find it?
First up, what is it?
Bokeh (Bo as in bone - keh as in kettle) is an umbrella term coined by Mike Johnson of Camera and Creative Darkroom Techniques magazine in the ‘90’s (still very active as The Online Photographer blog) and John Kennerdell, a then resident of Japan who broached the subject with Mike after noticing it mentioned in several Japanese lens reviews.
This lead to a full magazine edition (no small thing) dedicated to the subject (May/June ‘97 edition of “Darkroom and Creative Camera Techniques”- see Books and Bags for a full run-down). They (Mike) created the name using the Japanese term Boke (the “h” was added for pronunciation-not that it helps often) that refers to the “quality or flavour of the out of focus elements of an image”, used by the Japanese in painting. As with many words or terms, it can take on other meanings such as being “fuzzy headed”.
In photography it is especially useful as the very real photographic phenomenon of out of focus and transitional focus areas are found in almost every camera made image.
Almost no photography (flat object copy work and astro photography excepted) is entirely and equally in focus at all points of the frame, so some, much or most of any image taken with photographic tools is going to to be either slightly or more that slightly out of focus. This is called out of focus blurring and is part of depth of field. The character of this transition varies greatly in form and personal preference, but regardless, it all comes under the general term of Bokeh.
Where it has gone wrong in recent times is in interpretation. Bokeh has become a term used almost exclusively to describe super shallow depth of field and simple optical phenomenon such as totally blurred “Bokeh balls”, but that is like mixing up flavour intensity with flavour type. Shallow DOF is simply a reality of physics. Longer lenses, wider apertures, higher magnification, greater relative distance to the background, all contribute to the effect of shallow DOF.
The term Bokeh refers to the quality of that blur, not the quantity.
Many photographers have been responding to Bokeh or the different rendering their lenses create since photography became main stream, often proudly stating that an image was made with lens “X” rather than “Y” based on a “feeling'“ or sharpness rendering of the favoured lens, but this was more from an awareness of individual lens character, not a defined or a specific measure. They were often responding to the Bokeh, without having a recognised term to describe it.
The difference in Japan is there is a defined set of terminologies that can be and are used regularly and seamlessly. “Ni-Sen” for example referred to “cross-eyed” or double lined Bokeh. The problem for us stems from the lack of an over-arching term to describe all of these individual types of blurring in a way western users could understand. The term Bokeh unfortunately describes the phenomenon, not the individual set types within it, but has become the one term we use to describe…what exactly.
What effect does it have?
The reality is, we respond to it whether we are aware of it or not. Have you ever used a lens that makes images that just look right, especially when there is a lot of out of focus information in the composition? Maybe another that, for some reason you dislike on a fundamental level, but you are not sure why? Chances are this is Bokeh at work.
The right and wrong of it are very subjective. One persons need for silky smooth, even blobby” backgrounds is at odds with a another person’s “story telling” long transition rendering.
In the past, mainly due to technical realities of slow films on larger format cameras (both contributing to shallow depth of field as a constant reality), lenses were designed to show deep and graceful transition. As cameras got smaller and film faster, tastes changed. Shallow depth became a creative tool rather than an avoided curse and our preferences for Bokeh changed also.
The two images above were both taken with different 25mm lenses at the same distance with the same f2.8 aperture (slight difference is down to the modern lens being actually slightly wider than marked) and the same camera. The thing to look at here is the rendering of the hose and flowers in the background.
The left image was taken with an old Olympus Pen lens from the 60’s, where the extra (micro) contrast and complication of the image would have possibly been seen as a benefit. The right hand image was taken with the newer Olympus 25mm f1.8, a lens that shows lots the modern trend of fast-smooth transition favoured by many. The actual sharpness of the two lenses is similar.
You can ignore Bokeh, but you cannot escape it. Some photographers, such as landscape specialists have less need to worry about the Bokeh of their lenses, as they tend to shoot with maximum DOF, but many other forms of photography, such as portraiture play in this area constantly.
Next time you are responding positively or not to an image, consider the Bokeh as well as other compositional elements. It may be the core of an emotional response rather than a purely technical one.