Videoscopes: How They Work

When we are out there shooting video, we would like to have consistent color and brightness for all our shots. In some situations we may not be able to achieve the desired consistency because of time or equipment constraints. Still, we go on shooting because we know we can fix inconsistencies in post-production through the help of videoscopes.

Most good video editing programs come with controls to tweak hue, color and brightness. These controls are important especially for those of us who need to submit video for broadcast. This article will discuss the four types of videoscopes that’s important in post-production. They are the waveform monitor, the vectorscope, the histogram and RGB parade.

The waveform monitor in your video editing program displays the relative levels of brightness and saturation in your video. The reading comes in the form of percentage and moves from left to right. Zero per cent signifies absolute black and 100per cent is absolute white.

Some video cameras can shoot above the absolute white level and move into super white. While this may be useful for web video, it would not go down well when it comes to producing video for broadcast. You could minimize the problem through the help of the waveform monitor.

The vectorscope comes in the form of a radar monitor with a crosshatch with circles spreading out from the centre. It gives us information on hue and colour saturation. There are six squares in what looks like a normal colour wheel. These squares are called targets and they highlight RGB (Red, Green, Blue) also called the primary colors and also cyan, yellow and magenta – the secondary colors.

Saturation is measured from the centre of the circle to the box. If a colour overshoots the box (target), then it’s deemed oversaturated for television broadcast. You would then have to use a broadcast safe filter to keep the saturation within a safe range.

The histogram would come useful if you want to check the exposure level of your video and the contrast between images. It gives an indication of your luminance level starting from zero (absolute black) to 100 (absolute white) and 109 per cent (super white).

The spikes, valleys and peaks will indicate the pixel count of your video image. If your clip has low contrast, then you will see a gathering of pixels in the middle. If the contrast is high, then you will see the pixels collected at the extreme left or right.

The parade scope works like a waveform monitor but with a major difference. You get an overview of your video image saturation. But then the scope singles out the RGB (Red, Green, Blue) aspects of your video and lines these colors one after another in other words, parading them.

This is a neat feature as it allows you single out and on work on individual primary colors.

This article provides you with just an overview of videoscopes. To gain a better understanding of how they could enhance your video projects, you should take the plunge and spend a day or two tinkering with them. Experimentation and learning what works first-hand is a surefire way to learn the `inside secrets' of videoscopes.