In the world of videography, bokeh is a term used to describe the visual quality of the blur area outside the focal point which seems to separate the main subject from the background. Visually, our eyes are stunned when we see a video with a sharp and focused main subject with a soft, crisp, and beautiful background. Why are you stunned? because the main subject stands out while the blurry, creamy background reinforces the impression of dimension and depth. So how do we get bokeh videos every time? The following are below tips:
1. Use a lens with a large aperture
Bokeh is determined by the lens, not the camera. The lens and the optics in it determine the quality of the bokeh that the video produces. So use a lens with a setting at the largest aperture. For DSLR and mirrorless cameras, you can use the aperture priority mode on the camera, then set the lens f-number to the smallest number. On a lens with the f / 2.8 specification, for example, use f / 2.8 instead of f / 4. In the kit lens with an aperture range of f / 3.5 – 5.6, use it at f / 3.5.
What is the effect of the settings above? basically by enlarging the aperture (using the smallest f), we narrow the focus space very thin, while the rest looks blurry and out of focus.
If you are using a smartphone with 2 lenses, choose a telephoto lens and use portrait mode.
2. Closer the distance between the lens and the video subject
The closer you are to the main subject, the more blurry the background will be. Why can? because when the main subject is very close, the focal point of the lens gets closer and the depth of field becomes thinner. Want to try it with lenses in your eyes? try to put your index finger in front of the face and try to focus on that finger. Then pull the index finger closer to the eye while staying focused, what happened to the background behind it? more blurry isn’t it!
Video lenses work on the same principle. The closer the subject is to the lens, the more blurry the background behind it will be.
3. Keep the main subject against the background
When the subject of the video is too close to the background that looks busy, the resulting bokeh will look ugly and busy. Why? because the background is still in the focus space of the subject which still looks sharp. The video’s sharp space moves from focus to blur gradually, with gradations, not just skips. So the deeper the background is from the focal point, the softer and more blurry the background becomes.
Take a look at this foliage video. The focal point of the lens is on the front leaf, the more behind the leaf (protrudes from the focus point), the more blurry the leaf looks.
4. Use the Longest Zoom
With the distance from the camera to the video subject the same, using the zoom lens on the longest side will automatically reduce the sharp space of the lens, making the background even more blurry. So when you use an 18-135mm zoom lens, use it at 135mm. When using a 70-200mm lens, use it at 200mm and beyond.
5. Use a Telephoto Lens
Because using a longer focal length means reducing the depth of field and increasing background blur, automatically using a telephoto lens helps us achieve nicer bokeh. Assuming the same optical quality of course.
The video above was shot with a 650mm lens, so the background is almost perfectly blurred.
6. Use the fastest lens you have
If you are obsessed with perfect bokeh, try shooting with a bokeh factory lens like a 50mm f / 1.2 lens, or an 85mm f / 1.4 or 135mm f / 2 or 70-200mm f / 2.8 when used at 200mm.
You can get information about other bokeh videos here video bokeh museum.