背景虚化 (Bokeh)

如果你患有近视，必须戴眼镜，必定有脱下眼镜后视觉一片模糊的朦浓经验。这是很不舒服的，可是如果你在夜里不需要驾驶 ，试试把眼镜脱下，你会看到一片街灯与车灯互相辉映的朦浓美丽景象，如幻似梦，灯光都成为大小不一的光圈，煞是好看。

如果在这片朦浓夜色之中，出现一张清晰的脸孔，这张清晰的脸孔与朦浓的背景，将会构成一张让人印象深刻的图像，看后会有种特别舒服的奇妙感觉。

单反摄影其中一种摄影手法就是特意让背景虚化，让摄影者在朦浓的背景中，得以突出清晰的主题。

这种背景虚化效果构成的摄影作品，是我最爱之一。


As extracted from Wikipedia, the following describes what is ‘bokeh’:

In photography, bokeh is the blur, or the aesthetic quality of the blur, in out-of-focus areas of an image. Bokeh occurs for parts of the scene that lie outside the depth of field. Photographers sometimes deliberately use a shallow focus technique to create images with prominent out-of-focus regions.

As a layman, I do not bother about the theory and explanation behind it. However, I do find an image with suitable background (or foreground) blur pleasing. It makes the subject stand out and stunning as our focus is drawn onto the subject.

I am myopia since secondary school. I realize with myopic vision, when I remove my spectacle at night when my friend is driving me, I can see very blur but spectacular view of the street with a mixture of blur street lighting and moving lights of the moving vehicles. While I find the view spectacular, after sometime I will feel more comfortable putting back on my spectacle so that my vision is pin sharp again. However, it is not quite possible for me to view the scene with background and foreground blur but pin sharp on the object that I want to view.

In a photographic image, I can have both. I can blur the part of the image that distracts and turn it into a nicely blur background while make the subject sharp and clear, hence creating a final image that is visually very pleasing to look at.

This is another reason why I find DSLR photography interesting.