The Bokeh is a Japanese word that refers to the aesthetic quality of the blur depth of field. Simply put, bokeh is the texture aspect of that blur.
Since you are French-speaking, let's draw a parallel with cheese, it will speak to everyone 😉 Let's take reblochon with its creamy texture and fairly mild taste (without the rind), which is very different from a 24-month Comté, whose texture is more dense, and the taste quite spicy with aromas of hazelnut. You have the right to prefer reblochon to Comté, it's a matter of taste!
Well for the bokeh, it's the same! You may like the soft and balanced bokeh , or you may prefer the ones with more complex textures. Bokeh is the aspect of blur: it's a matter of taste, therefore a necessarily subjective notion.
The depth of field , in turn, refers to the size of the depth of field and thus the amount of blur (in front of and behind the subject). Since it is a question of quantity more than of quality, it is a characteristic of the photo, and therefore a more objective notion.
Small example to understand. In the photo above:
- The depth of field is shallow. It is undeniable, no need to invite two experts to have a debate on this
- Bokeh may be judged harmonious for some, too distracting for others
- we should not say "a lot of bokeh or little bokeh " if we stick to the strict definition
This is the theory of the school benches! In practice, be prepared to encounter language abuse very often : bokeh, background blur, and shallow depth of field are commonly used interchangeably!
In this article, I'm going to talk about the primary meaning of bokeh - to help you better control its aesthetic appearance in your images.
What is a good bokeh?
As you know in photography, you are responsible for what is in your frame. This means that nothing should be left to chance in your choices.
Depth of field is one of those choices.
The shallow depth of field is a very useful tool for drawing the eye easily to the subject of a photo, and eliminating extraneous elements in the blur. This is also why it is often used in professional photography to ensure that a photo shows what the customer wants.
As you might expect, there is no shared definition of what a 'good bokeh' is, but in light of the above it could be seen as a background blur that looks consistent with the intent of the photo.
In other words, bad bokeh distracts attention from the main subject of the photo and weakens it, while good bokeh makes it stronger.
I know, you are going to say to me " it is very nice all these beautiful sentences, but can we see concrete photos to understand please? "
And you are right ^^ Here is a non-exhaustive inventory of the different aspects of bokeh and their interest to serve the image composition and your photographic intention.
Small warning, however: what will follow is by no means a cooking recipe that must be followed to the letter. You know my opinion on the over-simplification of the advice related to the construction of an image (of which the rule of thirds is the emblematic example).
Note also that this classification of the different types of bokeh is not governed by any standard and is my sole responsibility ^^
The silky bokeh
Silky, creamy, smooth, I'll let you choose the adjective that speaks to you.
It is a fairly uniform color and texture blur (typically a single color cast)
We find this soft bokeh sometimes in a tight portrait photo, where only the subject is in focus.
This type of bokeh works well when the background does not provide relevant information to the photo, and its purpose is to bring the viewer's full attention back to the subject. As such, it has the same function as the plain backgrounds in studio photography.
Sometimes even the area of sharpness is so narrow that it is limited to the subject's face when his ears are already blurry! In this case, you have to be careful with the focus.
This very soft bokeh rendering is all the easier to create as the focal length is long, the aperture is large, and the background is far from the subject and of a fairly solid color (it will work less if you have bright reflections of the sun on the background). Maximize all parameters.
For example on Full Frame, a 200mm f / 4 or an 85mm f / 1.8 are suitable.
To have the same rendering on micro 4/3, it will be necessary to compensate a little for the size of the sensor by increasing the aperture. For example, with Panasonic Lumix GX Vario 35-100mm F2.8 II Power OIS , you reach without worry a 200mm f / 2.8 equivalent which will do just fine 😉
You will notice that we see this type of bokeh a lot in sports or wildlife photographers , who are accustomed to very long focal lengths (and at the same time, they do not necessarily have the choice, being parked at the edge of the field!)
The bokeh with small bubbles of light
Yes this name is not absolutely unofficial, it's normal, I just made it up 😅
It is an archi-ultra-classic rendering of bokeh that you have surely seen before , and which consists of blurring small sources of light present in the background: typically city lights, garlands on a Christmas tree or candles.
This type of bokeh contributes to the ambiance of the scene. I remember that I was absolutely a fan of it at the beginning of my practice to the point of using and abusing it 🙂
You are the only captain on board: it's up to you to dose this effect sparingly and see if this rendering is in accordance with your photographic intention!
Finally, you can also get this type of rendering in the forest, in the middle of the day, when the sun creates reflections on the leaves of the trees. Moreover, it can be a good way to continue photographing in the middle of the day, when the sun at its zenith produces unsightly shadows on the faces of your subjects.
To give you an idea, this is how the background changes when I change my focus distance from several meters to around 1m, at 200mm f / 4. Again, do your tests with your own equipment to find your bearings, but at least you know that you have to take your basket and your device when you go to look for mushrooms in the forest 🙂
To make these light spots more "creamy", manufacturers like DZOFILM, Sigma, Samyang sometimes add an additional optical element in some of their lenses: the apodization filter 🤨
The idea here is not to swoon over the technology itself, but rather to give you the necessary info so that you know what it is if you ever hear about it:
- this additional filter (called apodization filter or APD) often concerns focal lengths dedicated to portrait (typically 80mm or more in Full Frame equivalent)
- it has the effect of smoothing out the bubbles of bokeh lights, to further soften its overall texture (as with reblochon, you remember 😉)
As I do not have this kind of lens on hand, here is a diagram of a light bubble modified by an APD filter. Note that the lens used for the foliage above does not include an APD filter, and you can see that the rendering of the bokeh bubbles is not more catastrophic 🙂
Moreover, this technology is quite recent since not all brands include it in their range. We can cite three:
- Fuji 56mm f / 1.2 APD
- Sony G Master 100mm f / 2.8 STF
- Canon RF 85mm f / 1.2 DS
The entry ticket exceeds 1300 euros for this type of lens so let's say that you really have to want to soften these little bubbles of light to decide to invest 😉
But back to the topic of this article, with the penultimate bokeh look.
The light bokeh
It gives a glimpse of the background distinctly enough to give context to the scene being photographed.
For example, this photo of an anonymous dock worker in Liverpool shows us a barely blurred background that suggests strike action in the face of difficult working conditions.
This type of bokeh is also common for backgrounds with repeating patterns as in the photo below with the bayonets of the soldiers. The viewer's imagination reconstitutes the background, without it attracting too much attention to the detriment of the subject.
In conclusion, I would like to invite you to see bokeh as one tool among others in the service of your composition!
At the beginning of his practice, we discover the wonderful world of shallow depth of field and we make bokeh to make bokeh, which is quite normal.
Personally, I'm not obsessed with rendering the bokeh of my lenses, and rendering a 50mm f / 1.8 equivalent is already more than enough for me!