A Quick and Simple Bokeh How-To

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During our photo club’s decoration shoot this year the number one question I heard was along the lines of “how do I do that shot with the lights around it?” so I’ve thrown together a quick tutorial. This post is targeted toward beginner/intermediate, so I’m going to do my best to steer clear of the really technical stuff in favor of the plain basics.

Bokeh Shot Basics

In this shot we’re going to put our subject in front of a background of colorful circles. The whole trick is to have the subject be close enough to the camera so that it’s in focus while the lights are far enough away that they will be out of focus.

There are multiple approaches to the bokeh shot, but for simplicity, we’re just going to focus on this one.

 

What You’ll Need

  • christmas lights (or something that makes little points of light like that)

  • a small subject (I had a roll of film handy)

  • a flat surface to work on

  • any lens will do, but something in the middle (around 50mm) will make this example easier to follow along with

 

The Setup

Set your lights in a pile and try to spread them out a bit.

Place your subject between the pile of lights and the camera. You may also want to put some kind of light on your subject to brighten it up (and to make focusing easier). I’m using a flash, but a flashlight pointing at your subject would work too.

Frame up your shot so that the lights fill the viewfinder with the subject between them. If you focus on the lights it’ll look something like this.

Now set the focus on your subject. You’ll probably need to use manual focus for this because your autofocus may try to focus on the lights (which is the complete opposite of what we need). As your subject comes into sharp focus, your points of light will defocus and turn into soft circles. Looking through the viewfinder you will see something like this:

 

If your setup looks similar to this, you’re almost ready to shoot!

 

The Camera Stuff

I said I would keep the technical stuff to a minimum, and I’m trying, but to make this work reliably you do need to put your camera into full manual mode and change the shutter speed, aperture, and ISO settings. You’ll get those settings in just a moment, but if you if you need help with how to adjust your camera’s settings you should refer to your manual.

These will vary depending on the power of your lights and your camera lens, but here’s a good starting point:

  •  Shutter Speed – 1/100th
  • Aperture – The widest (smallest number) your lens will go to. Might be 2.8, 3.5, or somewhere close to that. It changes with your lens. If you see 11, 16, or higher then you need to head in the other direction.
  • ISO – 800

When you have those settings dialed in, dim the room (if you can) and take a test shot. What you’re looking for is the color and brightness in the bokeh. It’s subjective, so it’s up to you to figure out what you’re happy with.

If your test shot is too bright, change the shutter speed in the faster direction to darken the image. Set it to 1/200 and try another test shot. Repeat as needed.

If your test shot was too dark, change your shutter speed in the slower direction. Try 1/50 and see how that works. If it’s still too dark, try 1/25 and repeat the test and adjustment until it brightens up to your liking. (If your shutter speed gets too slow, you’ll need to use a tripod to keep your images sharp.)

When you get your shutter speed set right, you should see something like this:

Once your bokeh looks good, it’s time to worry about lighting the subject. If your subject is too light or too dark, fix it by adjusting the amount of light you are putting on the subject rather than changing your camera settings (any change to camera settings will affect how the bokeh looks.)

That’s all there is to it! Once you get the basic concept down it’s easy to apply it to different situations. We used a small subject, but there’s no reason you couldn’t have your subject be a person if you just up the scale. Instead of the subject being a foot away from the camera and the lights being 3 feet away from the camera, you may have your person 5 feet from the camera and the lights 15 feet away.

 If you’re happy there, go shoot and have fun! If you want to get a little more in depth on why this works, keep reading.

 

Let’s Get (Just a Little) More In-Depth

Here’s the setup with some simple overlays to help visualize what’s going on:

The focus is set on the roll of film. Depth of field (the area in acceptable focus) is the green area that lives around the the spot where you set your focus. (This area gets larger and smaller with your aperture setting which is one reason wider apertures are easier to use for this technique – larger apertures give you less in-focus area and smaller apertures give you more area in focus.)

Any lights within the green area would appear as points of light. As the lights are moved into the red area, they begin to be out of focus and turn into nice circles. The farther away from the green area the lights are moved, the bigger those circles become.

The distance from A to B is the camera to the subject. B to C is the subject to the lights. The smaller you make A-B relative to B-C, the more out of focus and larger those bokeh discs will be.

Shooting the lights as they trail off along the floor you can see how they go from in focus, to softer and larger discs of light. Notice the shape of the bokeh changing to little footballs as it gets closer to the edges. This post won’t go in-depth on that aside from saying that she shape of the bokeh takes on the shape of the hole the light passes through on the way into the camera.

You Could Reverse the Subject and Lights

You can do the bokeh shot with the lights closer to the camera and the subject farther away. The trouble there is that the wires and such may be in the way of your subject. They may not be too visible, but if you’re shooting through them they will have some impact on the quality of the subject.

Bokeh Shape Changes

The bokeh will take the shape of the opening the light passes through on the way into the camera. Most of the time you want to do these shots at your widest maximum aperture because that’s where your lens opening is the closest to being a circle. As you use smaller aperture settings, the shape of the aperture in your lens takes on some corners and it’s not long before it has a definite polygon shape and so will the bokeh it makes.

You can clearly see the straight lines in the opening inside the lens. Shooting bokeh like that will result in harder lines like these:

Notice this one has the lights in front of the subject? I had some battery powered lights dangling directly in front of the lens. Distant subject in focus means close lights will be out of focus.

Dirt!

The dark spots inside the bokeh is from dirt either on the back of the lens or on the sensor. I hope you have fun playing with bokeh. I’ll be off cleaning my sensor…

 

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One Response to A Quick and Simple Bokeh How-To

  1. TKSharpley says:

    GREAT TUTORIAL!!!

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