Video Composition
Depth of Field:
Creative Ways to Control Your Audience's Attention…!


Video Composition Depth of Field

 Controlling and creatively using depth of field in video composition is the mark of a true professional...! Let's take a look at some of the ways you can use this…!


Definition: Depth of Field

Definition...

* Depth of field is the range of distance that appears acceptably sharp when you are looking through the viewfinder or at the LCD screen.

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That is an important point…

Depth of field tip

* "It is the range of distance that appears acceptably sharp to you the camera operator".

Meaning…

Depth of field – personal preference of cameraman

* It is really a matter of personal preference (and the consideration of what kind of effect you're trying to create) as to what is acceptably sharp in the picture.

What do you want your audience to see? As in all video composition , depth of field is really quite subjective! The "acceptable" depth of field will differ from one person to another based on what you want visible in the frame.

Depth of field soft background and foreground

In video composition depth of field in any shot or scene will be determined by where you want your  audience's attention to go and/or what type of emotional environment you're trying to create.

Controlling depth of field along with the right camera shot and camera angle will help you to create a precise effect on your audience.

Working with the Depth of Field In Your Shot…

The depth of field in any shot or scene can be varied in several different ways.

Depth of field – further definition

 If we further define depth of field as...

* The zone of sharpest focus in front of, behind, and around the subject on which the lens is focused.

We can then start to get some ideas on how we can vary the depth of field in the shot so that it can be used creatively in our video composition. But... How do we actually control  the depth of field so we can use it creatively?

Okay... let's take a closer look at three of the main ways to control depth of field:

*Adjusting Aperture Setting

*Distance from the Subject

*Focal Length of the Lens

Controlling Depth of Field with the Camera's Aperture Settings…

What is an easy way in video composition to control the depth of field?

video composition depth of field

Well… On the higher-end professional cameras we could first work a bit with adjusting the aperture setting of the camera.

This is done by changing the diaphragm opening (f–stops) of the lens.

Here are some examples of how you might go about doing this:

If it is a given  (a fact)... that we have the subject at the same distance and the same image size... Then the larger the lens opening (the more light you let in) the smaller  the area of depth of field.

In other words… The area to the front and the back of the subject will tend to be out of focus. Of course ... one of the drawbacks may be that the zone of sharpness will be more limited but... It can be a plus however that you'll be able to shoot in lower light.

Now... If you go to a smaller aperture setting (allowing less light in) you will have a deeper (more area in focus) depth of field. But, of course will you have enough light to shoot at that f-stop (aperture) setting? If you work with this a bit and understand it you should be able to use it very easily when you're composing and shooting a scene.

Knowing your camcorder Lux ratings and the camcorder light sensitivity will help you when you're making your decisions about using the aperture setting to control the video composition depth of field.

Controlling the Depth of Field by Varying the Distance to Your Subject…

Another way to control depth of field is to vary the distance  between you and the subject you're shooting.

Depth of field – rule of thumb #1

The Rule of Thumb on This Is…

* The closer you get to the subject of the shot – the more the zone of sharpness in the background and foreground will diminish.

depth of field soft background

And of course the opposite is true...

  • The farther away you get from the subject of the shot – the greater the depth of field (zone of sharpness front to back) you see in the shot.
depth of field sharpness front to back

This is a simple but very effective way to control the depth of field in your shot as you can quickly see in your viewfinder or LCD screen the depth of focus as you move in and out from the subject.

Now… If you really want to shoot your video like a Pro…

Controlling your depth of field this way can be precisely planned out as part of the script and then storyboarded out as far as types of shots and camera angles and the effects you want to create with each one of them. You can have a lot of fun with it!

Using a Zoom Lens or Lenses of Different Focal Lengths to Control the Depth of Field…

* What is a prosumer?


A person who is not necessarily a professional but wants professional type features.


To use this aspect of controlling the depth of field you would of course have to have a camera that can use interchangeable lenses or a zoom lens such as:

  • * A "Prosumer" type camcorder...
  • Professional camcorder or...
  • A camcorder (with a zoom lens)...

If you do have one of these types of camcorders you can affect the apparent depth of field by varying the focal length of the camera lens.

Depth of field – rule of thumb #2

The Rule of Thumb here is...

* The apparent depth of field decreases as the focal length increases.

In other words, if you're using a zoom lens (for instance)...

  • If you zoom-in on the subject the depth of field (zone of sharpness around the subject) will decrease as the action of zooming-in increases the lens focal length.

And of course the reverse is true:

  • Zoom-out and the depth of field will increase as the focal length of the lens decreases.
Depth of field chart

Simple...! This method of affecting the video composition depth of field is probably the least impactful of the three as normally you be shooting at a fixed focal length but...

If you're trying to control your depth of field very tightly it's a factor worth taking into consideration especially if you are shooting with a zoom lens.

A Word about the Camcorder Light Sensor's Size and Depth of Field…

A common question…

Does the size of the light sensor within the camcorder make a difference in the control of depth of field...?

Camera Image sensor depth of field

Well... In my experience this is debatable and really doesn't have too much bearing on the controlling  of the depth of field.

The other factors such as distance, focal length and aperture setting have a much greater bearing on this.

For those who say that the sensor does have some bearing on depth of field the datum most often quoted is:

  • The larger the sensor you have in your camcorder the more you will be able to control the depth of field.

In practice… I haven't seen that the size of the camera image sensor is much of a factor in controlling depth of field but… I will leave it up to you to verify that for yourself… (smile).

Video Composition Depth of Field Pocket Guides…

Sometimes it's hard to determine the video composition depth of field just by looking through the viewfinder or LCD screen.

In that case there are pocket guides that you can use to mathematically work out the depth of field using:

Camcorder features depth of field
  • The distance from the subject
  • The focal length you're shooting at and...
  • The aperture setting desired

After you have the equation…

You be able to set up your camera and position it to achieve the desired video composition depth of field.

Most high-end camcorder lenses have markings on the lens barrel that will also assist you in determining depth of field.

Most of the time however you'll be able to see  (through the viewfinder or LCD screen) the sharpness front and back.

The Creative Use of Depth of Field In Your Video Productions…

Knowing how to use video composition depth of field can be very valuable…

Soft focus depth of field

The creative use of video composition depth of field can be used to draw attention to people or objects in the frame.

The audience's attention can be guided exactly where you want it by the creative use of depth of field.

Here are just a couple of examples:

  • One of the ways that this can be done is to soften the background so that the focus of the audiences attention goes on to the subject of the shot only.

Another way to use controlled depth of field in your shot is…

  • Selectively bring into focus subjects that are in the shot as the action continues. Allow the depth of field to soften in front or behind them so that the audience's attention is brought to the subject and is taken off of the background action.

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You can have a lot of fun figuring out ways to use selectively controlling depth of field in your filmmaking or video production.

You can really control the audience's attention this way and make it much easier for them to follow the action.


Remember it's your point of view that counts as far as the use of focus and video composition depth of field.

This type of use of depth of field is subjective and is up to you the filmmaker or video producer as to how you use it and what sort of impact you want it to have on your audience.

Be creative and…Have some fun with it!

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Have fun...!  Dan


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