May 29, 2008

Shooting Video Outdoors

Shooting outdoors is a challenge, because so many things can't be controlled. First and foremost, controlling the light is difficult. The quality of light provided by the sun changes during the course of the day, and you never know when a stray cloud will wander in front of your main light source. If the sun is bright, it casts strong shadows and forces people to squint, neither of which you want in your video.

Power can be very hard to come by when shooting outdoors. You can rent a generator or batterypowered lights, but this scale of production tends to be out of the range of most podcasts. You're probably going to have to make due with what you can carry and the light that is available. Bounce boards are invaluable when shooting outdoors, because you can use them to reflect the light from the sun and use it as a secondary light source.

Noise also is a big problem. You can't tell the world to be quiet, unfortunately, and you can't tell the wind to stop blowing. Fortunately, windsocks have been developed that you place over microphones to minimize wind noise. They look like big pieces of wooly foam and do a fantastic job. If you're going to do lots of outdoors work, windsocks are a necessity.

May 25, 2008

Thinking about Your Video Environment

The requirements of a video studio are very similar to an audio studio. You want a nice quiet location, with plenty of power. Video studios also require good ventilation, because lights generate lots of heat. You also should find a space with a high ceiling, both for the ventilation and for the lights. Surprisingly, it's best to find a space without windows.

The big power draw in video production is the lighting. Most lighting kits have three lights, with bulbs that are in the 500 to 1,000 watt range. For every thousand watts, you're pulling about an amp of current out of the wall. A three-point lighting kit can easily be pulling over three amps. So you need to make sure that you've got at least a 10-amp circuit going to your studio, because the audio, video, and computer gear also are going to need power. The last thing you need during your podcast recording is for the power to go out.

The bulbs used in lighting kits are fairly inefficient. Much of the energy they're burning up is given off in the form of heat. Point three lights at someone, and you're basically slow cooking them. Your video studio must have adequate ventilation, or you'll end up having to take breaks every 15 minutes to cool off.

One problematic side effect of ventilation is noise. Commercial HVAC (heating, ventilation, and air conditioning) systems are not installed with noise in mind. They hiss, rumble, and rattle all day long, which obviously is a big problem for the audio production. If you're lucky enough to be able to custom-build a space for your needs, be sure to let the contractor know that you need sound attenuation built in to the systems. HVAC noise can be reduced in many ways. It isn't cheap, but if you're building a studio from scratch, you may as well do it the right way.

Because video production is all about light, gaining control over your lighting is paramount for high-quality video production. Controlling the light involves not only where the light is directed, but also the color and quality of the light. For example, you don't want to mix different types of light sources, such as fluorescent and incandescent light. You also don't want to mix sunlight with artificial light. For this reason, it's best to have a video studio with no windows so you don't have to worry about sunlight. Windows also are a notorious source of noise, which is another reason to avoid them.

May 23, 2008

Video editing software & Accessories

Video-editing software
You definitely need some video-editing software to create your video podcast. Video-editing software allows you to edit your video, adjust the video quality, and do rudimentary audio editing (on some platforms). A number of editing platforms are available; these are some of the most popular:

Final Cut Pro (Mac): This is the flagship of Apple's video-editing suite.

iMovie (Mac): It's no Final Cut Pro, but for podcasts, it's probably all the video editor you need. And because it's from Apple, you can bet that there's tight integration with the iPod.

Adobe Premiere (PC): Adobe Premiere has been around since video editing on desktops began. It has very tight integration with Adobe Audition.

Sony Vegas (PC): Vegas is tightly integrated with Sony Sound Forge. In fact, Vegas has much of the audio-processing capability of Sound Forge built in.

Ulead Video Studio (PC):
This software has a great price and includes output templates for iPods and SmartPhones.

Cinelerra (Linux): That's right, now you can do video editing on your favorite free operating system.

Along with all the goodies discussed previously, you need a good selection of cables to connect all your equipment. As with audio, don't skimp on cable quality. You're better off buying an expensive cable that lasts longer. Depending on the scale of your production, you also may want to consider a number of other accessories. Many of these are used either to improve your video quality or to compensate for a troublesome video issue.

Processing amplifier (proc amp): Proc amps allow you to tweak the video signal in real time, saving you the hassle of having to do it later.

Camera filters: Filters can compensate for your lighting situation and thereby enhance your video quality.

Gels and diffusion materials: If you're using a lighting kit, gels and diffusion materials help you control your light.

Flags: Flags are used to direct light so it doesn't go where you don't want it.

Bounce boards: Bounce boards are used to reflect light where you need it. They can be as simple as a large piece of light-colored cardboard or custom-made versions that have different colors on either side to be used in different situations.

Video "humbucker": Video cables are susceptible to noise, particularly from nearby power cables. This noise shows up in the picture and degrades the quality. Humbuckers filter out this noise.

"Green screen" facilities: Using a technique known as "green screen," you can film your subject against a green wall or background, and then during the edit phase a different background can be substituted for the green background.

Gaffer's tape, clothes pins, cable adapters, etc.:
Every videographer has a kit bag full of adapters, tape, and lots of other things that are useful during a shoot.

Most of the items in this list can safely be skipped for your first few video productions. Most videographers' kit bags are the result of years of accumulation, having had to deal with a number of issues over the years. You should definitely make sure you have plenty of spare cables and a roll of gaffer's tape, because as the saying goes, anything can be fixed with enough gaffer's tape.

May 21, 2008

Video mixers & Video interfaces/capture cards (Video Production Tools)

Video mixers
If you're going to get fancy with your podcast and shoot with multiple cameras, you'll probably want to buy a video mixer. Video mixers, like audio mixing desks, take multiple video inputs and allow you to switch between them. They also offer special effects like picture in picture and cross fading between sources (see Figure 1).

Figure 1: Focus Enhancements MX-4 video mixer

Tip Of course, you can get the effect of a multiple-camera shoot by being clever with your editing. This common technique is used in news gathering, where the interviewer asks questions off camera while the interviewee is taped answering the questions. Then, when the interview is finished, the interviewer is taped asking the questions, and the result is edited to look as if two cameras were used during the interview.

Most cameras used for podcasting applications are camcorders, so they record the signal to tape. The video signal can also be recorded directly onto your computer via the FireWire output. It's always a good idea to record to tape as backup even if you're recording directly to your computer. If you're using multiple cameras and a video mixer, you also may want to consider recording the output of the mixer to a video tape recorder (VTR). Otherwise, you must digitize the tapes from all your cameras to recreate the live edit if something goes wrong.

Of course, you can purchase a stand-alone video deck, or more interestingly, you can now record straight to an external drive such as Focus Enhancements' FireStore (see Figure 2). These units record digital video from a FireWire cable so you don't have to digitize later. You just attach the FireStore to your video editing station, and it appears as an external drive.

Figure 2: Focus Enhancements FireStore FS-4

Even though many cameras come with flip-out LCD screens that allow you to monitor your video, these screens really aren't good enough for quality control. You should buy a small monitor (which in the video sense is a small video display) so you can check the lighting of your subjects. If you aren't shooting on location, you can use a television with an auxiliary input, but be careful: Televisions are built to flatter the video image and often are far out of alignment from the broadcast standard. If you go this route, buy one of the kits that help you calibrate your television display.

Video interfaces/capture cards
At some point, you have to get the video signal out of the camera and into your video-editing workstation. If your camera and workstation both have FireWire, you're in luck: All you need to do is connect them with a FireWire cable, and you can import the video data directly. If your workstation doesn't have a FireWire card, you can pick one up for less than $50 these days.

If your camera doesn't have a FireWire output, you can get a digital video converter box that takes an analog video signal as input and outputs a DV signal via FireWire (see Figure 3). The nice thing about having a digital video converter is that you can plug any video signal into it, such as a DVD player or old VHS player. Alternatively, you can buy a video capture card. Video capture cards take analog video as input and digitize it to your hard drive. Video capture cards range in price from under $100 to many thousands of dollars. For the most part, however, the convenience of DV cameras with FireWire outputs is hard to beat.

Figure 3: The Canopus ADVC-300 Digital Video Converter

May 19, 2008

Tripods & Lights (Video Production Tools)

A good tripod is far more important than you think. In fact, you should probably consider spending about one-fourth of your total camera budget on a tripod. Although it may seem hard to believe that a $500 tripod is that much better than a $50 tripod, the difference is immediately noticeable to a professional videographer. We learn more about the importance of a tripod later. For now, just put it on your shopping list.

When we're talking about video, we're talking about light. When you're shopping for a camera, you'll probably see all kinds of facts and figures about various models' performance under lowlight conditions. Don't believe them for a second. Manufacturers make all sorts of wild claims about low-light performance. The truth is that cameras don't work well in low-light conditions. The cheaper the camera is, the worse the performance.

Luckily, lighting kits are available for precisely this reason. Using a lighting kit gives you control over the light, which in turn gives you control over the quality of your video image. A decent lighting kit runs about $800 and comes in a snazzy flight case so you can lug it with you wherever you need it (see Figure 1).

Figure 1: A portable lighting kit (Lowel)

If you're on a really tight budget, you don't have to shell out for professional lighting. Shop lights purchased from your local hardware store can be used, though they don't have anywhere near the control that professional lights do. Typically, they produce a fairly harsh, unforgiving light but with creative use of diffusion and positioning, you can get lots out of a very small investment.

May 15, 2008

Video Production Tools : Cameras

Although podcasting was originally conceived as an audio-only medium, this is no longer the case. Video blogging, or vlogging, is currently all the rage and is bound to get more popular. With the ever-expanding deployment of broadband connectivity and the plunging costs of digital video cameras, video broadcasting is within reach of just about anyone.

Sort of. As powerful as modern digital video cameras are, the affordable "prosumer" versions can't create a broadcast quality video, at least not without a little help. When the digital video format first appeared in the 1990s, it was laughed out of newsrooms across the country because the quality was thought to be too crude for broadcast. Within a few years, the convenience and immediacy of the format has made believers out of even the most demanding television producers. These days, a good portion of reality television programming is shot using the digital video format.

Of course, it doesn't hurt that the quality of digital video equipment has improved since the first few cameras appeared. You can now find cameras that offer fine-grained control of the image, as well as cameras that accept different lenses. Even more exciting, with the advent of HDV (High Definition Digital Video), you can shoot true widescreen video on a budget that doesn't require venture capital. To begin, however, you're probably going to be looking at an inexpensive camera and some support equipment. This post surveys what's available at the moment and discusses what features you should look for when you go shopping.

Choosing the Appropriate Equipment
Video production has some basic requirements. Obviously, you're going to need a camera and something to mount it on (we explain later why handheld video is a no-no). Because video is all about light, your video quality depends on the amount of control you exercise over your light. This means you should have some lights at your disposal, along with bounce cards and flags to stop light going where you don't want it to go. You also need plenty of spare cables and some other auxiliary video equipment. Good video production starts with your camera.

A good camera is the single most important piece of equipment in your video signal chain. The camera records the incoming light, digitizing it and storing it as a digital video signal. The camera is therefore of paramount importance, much like a microphone is to audio. If your camera does a poor job of converting the incoming light into digital video information, you start off with lowquality video. Correcting digital video imperfections is very difficult. There are various methods of video processing available, but video is nowhere near as forgiving as audio. It's better to start off with high-quality video than to plan on fixing it later.

Video formats
The number of video formats available at the moment can be confusing to the neophyte. This is due partially to rapidly evolving digital video technology, and also due to manufacturers looking for an edge over their competition. Table 8.1 lists the most common video formats used in budgetconscious applications.

If you're just starting out, you probably want to start off with whatever camera is lying around or whatever you can borrow. If you're the slightest bit serious about a video podcast, you should consider investing in a decent-quality DV (digital video) camera. They're ubiquitous and have a number of features that are perfectly suited to digital video production. (These are discussed in the next section.) DV cameras are available at numerous price points, with higher-priced models offering higher image quality and better build quality.

What to look for in a camera
Digital cameras come with a bewildering array of features these days. Some of these are just marketing hype and of little use to anyone, never mind an aspiring video podcaster. Essentially, two main things determine the quality of your video:

Lens quality: Higher-priced cameras have better lenses, and better lenses provide better image quality.

Image capture mechanism: DV cameras use charge-coupled devices (CCDs) to convert the incoming light into a digital signal. The size and number of CCDs the camera uses determine image quality.

Cheaper DV cameras use a single CCD to capture the video, whereas more expensive versions use three separate CCDs and divide the incoming light into red, blue, and green components for a higher-quality image. You should look for a camera with three CCDs if you can afford it; the higher-quality video image is worth the investment.

When it comes to the lens, each manufacturer sings the praises of their lens for "superior color and image quality." Lens quality can be very subjective — it's usually a good idea to hit a few camera ratings sites to see what people have to say about the latest and greatest models. You can find a number of these sites: The granddaddy is

Other features you should be concerned about are listed here. The advantages of some of the features discussed here may not be very apparent when you first start out, but become important as you become more familiar with your camera and want to get the most out of its capabilities:

Manual adjustments: Many DV cameras hide functionality deep in an on-screen menu that may or may not be accessible after you're recording. Having buttons and switches easily accessible is a big plus.

XLR inputs for audio: You never want to use the microphone on the camera, because they're low quality and designed to pick up everything in the room. Instead, use a professional mic or two; these generally require an XLR input. Otherwise, you'll have to invest in an external add-on box to make the XLR cable compatible with the awful ⅛ mic inputs that some cameras have.

IEEE 1394 (FireWire) output:
A FireWire output allows you to transfer the video from the camera directly to your computer without requiring a video capture card. If a camera doesn't have one of these, don't even think about buying it.

There are so many cameras to choose from and so many mew models coming out every year that it's virtually impossible to recommend any particular models, for fear that they will be outdated by the time you read this! However, a number of cameras at the slightly more expensive end of the DV range are perennials. Even though Sony, Canon, and Panasonic keep bringing out new models, the cameras pictured in Figure 1 seem to stick around. They're all well proven by years of streaming video production.

Figure 1: DV camera workhorses: Sony PD-150, Canon XL-2, Panasonic HVX200

May 10, 2008

Using Podcast-specific Software : WebPod Studio

WebPod Studio
WebPod studio offers audio and video podcast production capabilities. It's available in three different versions ranging in price form $89.95 for the basic edition to $189.50 for the Enterprise edition. The main screen displays a number of icons along the top showing all the different things you can do, along with text links in the main part of the interface with links to wizards that walk you through each process. A sample screen is shown in Figure 1.

Figure 1: WebPod Studio helps you create audio and video podcasts.

WebPod Studio offers no advanced editing or signal processing tools, but it does offer a few features that set it apart. First, it offers teleprompting, so you can enter a script for your podcast. It also imports PowerPoint slides and converts them to slides you can use in a video podcast. It also creates RSS feeds and automatically sends your files to your server.

May 8, 2008

Using Podcast-specific Software : Castblaster

Castblaster is similar to Podcast Station in that it provides a simple user interface for you to create and publish your podcasts. A sample screen is shown in Figure 1. It also offers cart and deck functionality, enabling you to easily insert short audio pieces like sound effects or promotional pieces, as well as longer pre-recorded pieces such as songs or interviews. It has faders to control the volume of your microphone and your headphones, as well as the volume of the pre-recorded pieces.

Figure 1: Castblaster is a simple, no-nonsense way to create and publish podcasts.

Castblaster offers rudimentary editing, but does not offer any signal processing. Castblaster offers a publishing interface that automatically creates your RSS file, encodes your audio into MP3 format, and places the files on your server. It has tight integration with, because Castblaster is distributed by the good folks there, for $50.

May 6, 2008

Using Podcast-specific Software : Podcast Station

Using Podcast-specific Software
Assume you're using a standard audio-editing program to record and edit your podcast. However, a number of podcast-specific software packages include audio-processing capabilities, along with other capabilities that may be of use to you. This section discusses a few of these solutions. By the time, even more will be available.

Podcast Station

Podcast station, from Audion Laboratories, is based on its VoxPro software, which is a professional broadcasting package designed for recording and editing radio programs. Although it's priced at a fraction of the cost of VoxPro, it still offers a host of features that podcasters will find valuable. The Podcast Station interface is simple and intuitive. A sample screen from Podcast Station is shown in Figure 1.

Figure 1: Podcast Station offers radio station functionality in a single screen.

All your recording and editing takes place on the main screen. A large "button block" contains oneclick buttons for just about every operation you'll need. You can record from any soundcard input directly to the video time line and then insert songs, sound effects, or any pre-recorded files using the cart and deck buttons. After your program is on the time line, you can apply audio effects like EQ and compression.

Podcast Station is a well thought-out product with lots of nice touches. For example, if you rightclick any of the faders (Podcast Station calls them sliders), the fader does a nice quick fade out, for example if you need to cough or you want to quickly fade out from an interview. Right-click the fader again, and it is restored to its previous level.

Another great feature is the ability to undo. This is similar to the undo abilities of other audio-editing programs, but Podcast Station goes one better — you can undo days or weeks later. Podcast Station keeps track of everything you do and stores it in the file along with your audio, so you can undo all the way back to your original if you need to.

Podcast Station also has a nice wizard-driven publishing feature, shown in Figure 2. It automatically generates your XML file, compresses your program to MP3 format, and sends your files up to your Web site. On top of all this, the folks at Audion Labs have a good sense of fun that is reflected in the documentation and tutorials that are provided. This is hard to beat for only $59.

Figure 2: Podcast Station also offers encoding, RSS authoring, and FTP through its wizard-driven publishing interface.

May 5, 2008

Multi-track Audio Production

When you begin to create podcasts, you'll probably use a simple stereo audio editing program. As your productions become more professional, you may be tempted to move up to a multi-track audio program. Multi-track systems offer a number of benefits, the most important one being the ability to separate the elements of your podcast onto separate tracks. This, in turn, enables you to work on the tracks individually, applying tailored effects such as EQ and compression to each track on an individual basis.

Things to consider
Now that you're graduating to the world of multi-track recording, the first thing to do is label them appropriately so you know what is on which track. Sure, you say, I'm always going to put my mic on track #1, the guest on #2, and the music on track #3. Well, what happens when you add a telephone hybrid? What happens if you're sick and your buddy agrees to finish off one of your podcast productions for you? Believe me, it may seem pedantic, but labeling your tracks will save you lots of headaches in the long run.

Next, to take full advantage of a multi-track recording setup, you'll need an audio interface capable of multiple outputs and a mixing desk with multiple outputs. Each track can be assigned to a particular input, as shown in Figure 1. If you have only a stereo audio interface, you can still record to separate tracks, provided that you pan the two separate channels hard left and hard right on the mixing desk, and then record the left channel on one track and the right channel on another.

Figure 1: Sony Vegas multi-track software

After you have your audio recorded, bear in mind that the overall level will be cumulative. You have to be careful when you mix all your tracks together so that you don't end up with too much level. This can often happen if everyone talks or laughs at once. Suddenly, you have not one track but two or three, all feeding your master mix. This is why you'll want to think about using a compressor on each track or across your master mix if your software allows it.

Multi-track audio software is different in this manner, in that the effects you apply are not performed on the file. Instead, they are applied in real time as you play back the audio. In addition to being able to apply effects to each track, you can also apply effects to the master mix. In this situation, you could apply light compression to each of the input tracks and then a limiting compression to the master mix to make sure you never go into distortion.

Multi-track templates
If your podcast follows a particular format, for example if you use the same intro and outro music for each show, you can save time by creating a multi-track template that you can drop (or record) your audio into each week. Instead of having to worry about finding your theme music and worrying about levels, you just place the theme music on a separate track and then record the rest of your podcast on separate tracks. When you record using multi-track software, tracks that are not in record mode simply play back, so you'll hear the theme music in your headphones, and as it fades out, you jump in with your introduction.

May 3, 2008

When to Do Signal Processing

When to Do Signal Processing
Given all the signal processing options at our disposal, you may very well ask when they should be done and in what order. There really are no hard and fast rules, though we can provide some guidelines. The thing to remember is that the cumulative effect of all your signal processing is going to depend on how each step in your signal processing affects the next step.

For example, if you recorded your original audio at a low level, you may be tempted to normalize it to start. However, if you're planning to add some EQ, be sure to leave headroom, because you may add to the overall level. If you're going to use compression and EQ, remember that the compression is going to warm up your bottom end and make your audio sound fuller, so you may not need to add too much bottom end. Conversely, because compression is going to fatten your sound, you may be tempted to add a touch of high end to compensate for any lost sparkle.

May 2, 2008

Audio Processing Trick : Normalization, Noise Reduction,

Other Audio Processing Tricks
EQ and compression are the most common tools that audio engineers use to process their audio. But they're not the only tools, by any means. Here are a few more that you may find handy in your day-to-day podcast production.

Normalization means turning the audio up until the peaks are at a given level. This can be very handy, for example, if your record level is a bit low and you want to turn it up but not so much that it distorts. The simplest way to do this is to use Normalization.

Figure 1 shows the Sound Forge Normalization window. It's very straightforward; you can choose what level you want the file normalized to using the slider at the left. In this illustration, you'll see that we're normalizing to -0.5dB, not 0dB. You can simply normalize to 0dB, but if you do, you have no headroom. If you're doing normalization as your very last step, you don't need headroom. If you're planning on adding EQ, you should probably normalize to -3dB or even -6dB to leave headroom for later EQing.

Figure 1: The Sound Forge Normalization window

Of course, this is assuming you're using Peak Level normalization, which analyzes the entire file and raises the volume until the very highest peak is at the required normalization value. If you have one small section of the file that is loud, and the rest is very quiet, normalization is going to get you only so far. You'll have to use some compression to even out the levels throughout the file.

Another kind of normalization that's very handy if you plan on playing music is RMS normalization, shown in Figure 2. RMS normalization measures the overall power of a file, as opposed to just looking at peaks. If you combine this with an equal loudness contour, RMS normalization gives all your audio files the same apparent level.

Figure 2: Use RMS normalization with an equal loudness contour to make all your music files sound as loud as each other.

Note : RMS stands for root mean square, which is a mathematical measure of the magnitude of a varying quantity. RMS is calculated by finding the square root of the mean of the squares of a set of values.

Audio with lots of low frequency content sounds louder to us, so even though two files may "look" the same in an audio editor (both have peaks at -3dB), one may sound much louder due to its tonal character. RMS normalization using an equal loudness contour takes into account how sensitive our ears are to particular frequencies and sets levels accordingly.

Gating to remove background noise
A noise gate mutes the audio signal when the level falls below a certain level. For example, if you're doing an interview in a room with a noisy ventilation system, you could try using a gate to get rid of the noise when you're not talking. Setting up a noise gate involves setting a threshold and attack and release times, similar to a compressor, as shown in Figure 3.

Figure 3: Using a noise gate to remove unwanted background noise

Gating is best used when the background noise is very low; otherwise, the gating effect will be noticeable, because oddly enough our ears will notice the noise disappearing, and this can be more annoying than a constant background noise. If you have a serious noise problem, you may be better off using noise reduction.

Noise Reduction
Noise reduction is a sophisticated process that attempts to remove noise from your audio without affecting the rest of the content. As you might imagine, this is a very difficult undertaking. Noise reduction algorithms usually work by taking a "noise profile" or "noise print," which is used to determine the frequency content and level of the noise. Taking a noise print involves identifying a section of the audio file that contains only noise. The algorithm can then use this information to analyze the file and remove what it thinks is noise. Figure 4 shows the noise reduction windows for Audacity and Sound Forge.

Figure 4: Noise reduction, using Audacity and Sound Forge

You can see that both involve a two-step process — first getting a noise print, and then running the resulting filter across the entire file. Noise reduction can be incredibly effective for steady background noise. However, be aware that the urge to remove background noise can sometimes lead to audio that sounds too thin. The key is to use it sparingly, so that your audio sounds cleaner but not antiseptic and hollowed out.