PRACTICAL DV FILMMAKING

Practical DV FilmMaking

• Overview
• Inside video
• Films and how they work
• Pre-production
• Production tools
• Production aesthetics
• Post-production tools
• Post-production aesthetics
• Careers and distribution
• Mapping the industry
• Glossary of film and video terms

How the camcorder works

Before we look at the inner workings of the video camera, we need first to define what we are looking at. Not all cameras can record images; some simply pass them on to another device, which commits them to tape. In television, for example, cameras in the studio relay images elsewhere and so are not, technically, camcorders, just cameras. For simplicity, then, we will talk throughout this section about the kind that records images as well as seeing them, from entry-level consumer models through to those in the upper range used in filmmaking.

How images get onto tape

To understand how the image gets onto the digital tape, we could start at the beginning and follow the whole process. It basically runs like this:

• image through the lens

• image is sensed by a CCD chip

• gets translated into binary code

• then gets transferred to tape.

Surrounding this process are a range of features that help modify the image, making it clearer or more stable, if needed. Audio signals recorded simultaneously go straight from the microphone,

getting translated into digital information and onto the tape, and are matched with the images accom­panying them.

What happens when the image hits the lens

Lens

The lens is the point at which the image crosses into the camcorder, using an iris which functions much the same as the human eye. Lens quality is crucial; the camcorder may have a perfect method of recording what it sees, but to make the most of it must see perfectly to begin with. Consumer-level camcorders will not usually have the lens quality of those in the semi-professional and professional range levels, although some manufacturers try to improve the lenses on cheaper models by teaming up with established photographic lens makers.

Iris

The iris in the lens controls the amount of light entering the camcorder and will quickly shrink if too much is entering or dilate if there is too little. The reason it must do this is to satisfy the amount of information required by the CCD chip situated near the lens. If there is too little light and the required pixels do not each receive instructions, then the chip steps in and starts adding its own default informa­tion. This is known as 'noise' and is read as tiny white dots all over the screen, which is why you get a grainy image if you shoot in low light conditions.

Shutter speed

The shutter and the iris overlap in their roles to some extent