Making a Demonstration Video for E-Learning Use

Lighting for video

“Lights … Camera … Action!” Any video starts with this. And there’s a reason that lights come first. Without light, there is no image. No matter how much you spend on a camera, tripod, or other equipment, if there are no lights, there is no image and hence no video. So what about lights? What kind do you need?

If your video is only going to be shot outside on a sunny day, then you don’t need any other lighting, except for maybe a reflector. In this case, a piece of white cardboard or Fome-Cor™ makes a fine reflector. If, like the rest of us, you shoot indoors or on cloudy days, you need some lights.

This is what you need for a basic kit. You can buy a kit, or you can put one together.

Three-point lighting

Good kits are designed to support Three-Point Lighting so they have at least three lights: one key light, one fill light, and one back light. Three-point lighting is a method of lighting an object or person that emphasizes the three-dimensional qualities of the subject as it moves through time on a two-dimensional field.

1. Key light

The Key light is the primary source of illumination on the subject. In a “studio” shot, the Key light will be near the camera, 10 to 30 degrees off center from the camera. This light is just enough off the camera’s “line of sight” to support the illusion of depth of field. The Key light should shine down on the subject at a 45 to 65 degree angle. If the shot replicates a natural light like a window or the sun, the Key light goes in the logical position that supports the illusion of natural lighting.

2. Fill light

The purpose of the Fill light is to soften the edges of the shadows created by the Key light. Place the Fill light in an opposing symmetrical position to the Key light. If the Key light is 30 degrees to the left of the camera, the Fill light should be about 10 degrees to the right.

The Fill light is typically not as bright as the Key light. The Key-to-Fill ratio is usually 8:1 which means that the Fill light is 12.5% as bright as the Key light. Three-point light kits come with lights of the proper brightness to produce this ratio. You will not have to worry about light levels as long as the lights are set in a normal three-point light configuration.

3. Back light

The Backlight is the light that projects an edge of light around the contours of the subject. This light does not illuminate the background. It lights the back of the subject or object. Place the Backlight 180 degrees from the Key light. The Backlight assists the viewer in understanding the exact edge of the subject. Without the Back Light, the subject would fade into the background, making it difficult for a viewer to understand the shape of the object.

It’s a very good idea to purchase a Three Point Light Kit as it makes it easy to effectively light a video production. There are several options for the light sources themselves.

Incandescent lights (Tungsten)

These look like regular old light bulbs, but they are a little bit bigger, and they provide a more balanced light than a regular light bulb. You can get a kit with the three lights you’ll need, along with stands to hold the lights and maybe a reflector, for about $100 to $125. You can also spend $400 for essentially the same thing, so shop around for the best price. The main problem with incandescent (Tungsten) lights is that they tend to burn more orange as they age. But they are inexpensive, so you can keep the bulbs fresh without much expense.

Halogen

These lights are more expensive than the incandescent, but they have several advantages, and one or two disadvantages. The first advantage is they are brighter. And bright means you can see more and control more. They also don’t yellow as they age. They are much hotter though, and every once in a while they burn out with a bang. However, most of these lights come with a screen that goes over them, so there’s no worry of injury. A good kit, by Lowel, will include two Fill lights (one for Backlight and one for Fill) and a Key light), stands, and a reflector or two. It will cost from $650 up to whatever you can afford.

These are the two main kinds of lights that you can purchase. I use both in different circumstances. In a small office, I’ll use Tungsten because they aren’t as hot. After an hour in a small room with halogen lights, you could be getting a little (more than a little) sweaty and tired.

New lighting technologies

There are some new lighting technologies in the marketplace, including Fluorescent and LED. Both of these have the advantage of operating very cool. Fluorescent lights that are used for studio lighting have good color balance, so you don’t get the green cast that most florescent lights give. LED lights have very good color and can be made into whatever color you want. Both of these light types are very expensive. LED spot lights start at around $1000, and that’s for one light.

Whatever kind of light you get, you’ll be right. Painting with light is quite a wonderful thing to do, and can take your video production to a higher level.

Camera support (tripod)

You’re shooting a video and need to keep the camera still. What do you get? A tripod, that’s what. There are all kinds of camera supports … monopods (one leg), tripods (what this is about), and various devices to help steady a camera when hand held.

This section is only about tripods, though. But it’s really about the part of a tripod that holds onto the camera; the head. The name “tripod” refers to the three legs, which provide a stable way to securely hold a camera off the ground. But you also need a head for your tripod. This connects the camera and the tripod. The tripod attaches to the bottom of the head, and the camera attaches to the top of the head. There are two kinds of heads: friction and fluid. Which is best for you and your use?

Friction head

A friction head has several advantages. The biggest advantage is cost. They can be very inexpensive, as low as $30 dollars, for a decent one. I don’t recommend friction heads, however, unless you’re not going to move the camera at all during a shot (and moving the camera includes zooming). These are friction heads that work simply by having two (usually metal) plates that squeeze together and a screw to make them looser to enable a repositioning of your camera.

Fluid head

A fluid head costs more, but has several advantages. A good fluid head can be had for about $150 and up. They work very differently than a friction head and make panning (moving the camera left to right) and tilting (moving the camera up and down) a smooth process, which is what you’d probably like for video. A fluid head has two chambers that are filled with a viscous liquid, with a plate in between the chambers. There is a tiny orifice in the plate that creates resistance between the two chambers. In a good fluid head, you can make the orifice larger or smaller to decrease or increase resistance.

Choosing the right head for video

Friction heads are usually best for still photography, not video. In still photography, it doesn’t matter if there is a little herky-jerky motion when you’re moving the camera. Camera movement with fluid heads is smooth because it’s easier to create smooth motion with resistance and fluid than it is with friction.

There is one other consideration: how heavy is your camera? If your camera is small, you’ll want a smaller and lighter head. Most tripod heads have a rating that indicates how much weight they can support. If your camera weighs two pounds, then a tripod head with a rating to support 25 pounds is obvious overkill.

Cameras

Once you decide to make a video, you will require a video camera. If you don’t own or have access to a camera you will need a budget to buy equipment (we hope it’s not too low). If you’re like most of us, you want to look at a camera first. So what does your camera need to have in order to make it right for your production?

My only “requirement” for a low-priced camera is that it must have an input (jack or socket) for an external microphone. You’ll want to be able to use an external microphone. Trying to use the built-in microphone on any camcorder (and this includes the high-priced ones) is courting disaster in your sound. Bad sound can make good video bad.

I have two more requirements. First, most cameras in the small, inexpensive realm now support HD (High Definition). While this is in and of itself a good thing, if you’re planning to show your video online as part of a training module, you DO NOT NEED HD. It’s total and complete overkill. The good news about this is that the chips in cameras that work with HD also work quite nicely with regular old standard definition (SD). In fact, their SD resolution is better than cameras of old.

The second item is media. For use in e-Learning production, I would suggest staying away from (at least at this writing in early 2009) anything except MiniDV tape cameras. Yes, there are all kinds of DVD cameras and hard drive cameras in the marketplace these days. But DVD and hard drive cameras compress video beyond what is good to edit.

There is a reason to my madness. Using compressed video involves uncompressing the video, and then recompressing the video after it is edited. Every compression cycle somewhat lowers the quality of the video. Almost all compression produces some sort of “artifacting.” This means you’ll see some blockiness when you pan, or the video sometimes looks as though it’s briefly breaking up.

A camera with a built in hard drive would be great, but if you’re out shooting all day, that drive can fill up. After shooting, you must move the video to the hard drive attached to the editing computer. Ultimately, using tape as the medium, and then capturing the video onto a hard drive, degrades the video images less than multiple digital transfers do.

Tape has another advantage. When you shoot in standard definition, you can capture files that are uncompressed (called “.avi” files). These .avi files can actually have better quality than High Definition files. Shooting in High Definition also has one other disadvantage (besides looking no better in an online experience). That disadvantage is that HD video is more difficult to edit and takes up lots more processing time and power. This is true even for highly compressed HD video.

Here are the specifications to look at when you’re shopping for a camera:

1. How good is the lens, and what is its zoom power (3X? 10X?)? This will be on the camera. You don’t want to use digital zoom, but optical zoom.
2. How many pixels does the chip have? An HD chip will have at least 1.1 megapixels, which is clearly too many for standard definition video, but it will help the overall resolution.
3. How big is the chip and how many are there? High-end cameras, those with a price starting over $2000, usually have three chips. That is one chip for each red, blue, and green channel. Your camera will only have one chip.

Formats or Codecs

Codecs … can’t live with them … can’t live without them. What are they and how do they work with an e-Learning video project? Simply put, a codec is a COder-DECoder. It’s a way computers save space with video files, which, uncompressed, are ENORMOUS.

There are codecs for showing video and codecs for editing video. You need codecs to show your video, whether on a DVD … that’s one codec …  or online … another codec … or for editing … yet another codec. You have probably already heard of two of these codecs, Quicktime and Flash video.

Quicktime (.mov files) is a codec that holds other codecs (as are a few others) so that you can still use it for editing (with one codec inside), then render it to another codec for purposes of placing on a DVD, and yet another codec for showing it on-line using Flash Video.

Flash video (.flv) is only good (and it’s very good) for placing in a Flash file (.fla) that will be turned into a .swf file that can actually be shown on the Web.

If you think the whole thing is confusing, you’re right! It is very confusing if you haven’t worked with it before. And even if you have, it’s still confusing sometimes. There’s more to codecs than Quicktime and Flash video, though.

Codecs are marvelously portable and changeable. They’re what make YouTube possible, and make your online eLearning possible as well. Codecs can take a very large video file that can’t be downloaded and make it into a file that can be “streamed” on-line. We’ve mentioned two common codecs above, but here’s a very short list of the most important ones for e-Learning:

• .flv — This is Flash video. You can’t just put video coded as .flv in a Web page. It must be incorporated into a Flash file that is then made into a .swf file that you can place in your e-Learning project.
• .mov — This is a Quicktime file that’s actually a container for other codecs such as the ones that follow in this list.
• h.264 — This is a highly compressed (read small file size) format that’s especially good for HD video as it keeps the file size manageable. Remember, though, that it’s hard to see a difference on-line between SD and HD.
• .avi — In a way, this is the granddaddy of all video codecs. The name is an abbreviation for “audio/video interleaved.” It was invented as a way to keep lips from saying the same thing as the audio. It can be inside almost any codec and can be turned into almost any codec.

If this is all really confusing to you, don’t worry. If you use the defaults set up in your software, you’ll probably get along just fine. It might not look like Hollywood, but then your camera probably didn’t cost over $125,000 either!

Conclusion

We hope this article has given you some useful information about the technology and equipment needed to make an instructional how-to video. Anyone could be forgiven for being a tad confused or even intimidated. This would only be natural, but don’t give up! Gather whatever equipment you can get your hands on and make a video. Use what you have, and embrace guerilla filmmaking for e-Learning production.

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