How Camcorders Work?
Here is an In-Depth Explanation
Thanks to the advancements in the digital video related technologies, there has never been a better time to shoot video and share it with your friends and family.
And the camcorder plays an important role to help you shoot and record videos!
The video camcorder is a fascinating instrument that lets us record on video some of the most precious moments in our lives.
Though it seems to easily capture and reproduce the videos, there are a lot of electronic components that work beneath the hood, unknown to us, as we happily go about capturing our videos.
Diagram taken from a Canon camcorder manual
Though it is not necessary for you to get into the details of how a camcorder works, understanding its working will help you appreciate the camcorder more. Besides, you will understand the problem better in case you have to get your camcorder repaired for some reason or the other.
CCD - Capture Images
A CCD - Charged Coupled Device is what captures an image on a camcorder. It converts light into electrical impulses from which the digital data is derived. If a camcorder has only one CCD, that single CCD has to create the whole image.
If you are looking for a professional camcorder, go in for a camcorder that has 3 CCDs - one for each of the primary colors, red, blue and green. These camcorders produce richer colors, but since it has 3 CCDs, the video camera will cost you more.
The Concept of Video Signals
After the light hits the CCD, a video signal is generated.
The camcorder's image on the CCD is made up of two sets of fields. These fields are divided into odd and even numbered scan lines. As the scanning takes place, each field passes to a second layer behind the CCD, known as the sensor layer. The sensor layer records each electric charge that makes up that field and then writes that information to the tape.
With digital camcorders, there is an added twist on that last step. A special converter inside the camcorder converts that electrical information into digital signals made up of bytes of data.
Features to Enhance Video Signals
Digital camcorders have special built-in electronics that enable the users to enhance and manipulate the video signal by adding effects.
Special electronics in the camcorder allow you to apply effects like electronic gain, black and white, sepia, fade, and so forth. Once the effects are applied, the processed video signal is then sent to tape.
What is Helical Scanning
The process by which the video signal is recorded to tape is called helical scanning. This is because video information is not stored as a straight line (linear). Rather, it is placed down at an angle; each frame is stored on tape at a slant. The basic idea of doing this is to save space on tape. Since every video also has the audio element attached to it, if all the information were to be stored as one consecutive line, you would need a lot of tape to store it! By recording the information at a slant and then stacking the stripes together, you get more information in less space.
Conclusion
I hope this write-up gives you some understanding of how the camcorder works from inside. Though from the outside, the video camera looks like a simple tool to use, but there is a lot that happens inside. Besides, if your camcorder needs any repair, knowing how the camcorder works will help you to understand the problem better.
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