Ok, so last time I wrote about getting traffic for images with the word “bokeh” in them, and I promised a how-to.

After thinking about it, I realized that I don’t really have a strong enough grasp of either optics or physics to pull off an in-depth, highly knowledgeable article on this.  For me, doing anything with bokeh is a bit of a crap shoot.  Intellectually, I get it – but I can only visualize it by feel, and I only know what works for me.

So, that being said, I’m slightly changing the subject: this is still a how-to, but it’s a “how to get a general feel” for bokeh.  Think of this as a training exercise, not a definitive lecture.

So, let’s start.First off: for creating nice, round bokeh-dots, you need quality glass. That is to say a good, fast lens.  And I do mean fast in the traditional sense: a large f/stop – 2.8 is the absolute smallest, but it’s better in the f/1.4 or f/1.8 range. I used a 50mm, f/1.4 lens for the shots below.

For exposure settings, you’ll want something that keeps the ambient light dark.  The bokeh is caused by lighter areas, and you don’t want to blow out the lights altogether.

So start by taking an in-focus shot (Fig. 1). Exposure is best in manual mode – I set it to -2EV for this. Next, change the focus to manual and very slightly move it out of focus (Fig. 2).

Fig. 1 - in-focus bokeh shot

Fig. 2 - Slightly out of focus

Notice that already we have a great shot, and this was barely tweaking the focus at all. Go ahead & give it a further tweak, then another:

Fig. 3 - further out of focus

Fig. 4 - Almost invisible bokeh

Here’s what I want you to notice: the further out-of-focus the light source is, the larger the bokeh circles.  The larger they are, the dimmer they are.

In fact, this is the key concept for today: all things remaining equal, the further out of focus the lights are, the larger and dimmer the bokeh.