Building the TV studio 2 years ago, it was relatively easy to choose the cameras. At the time, Standard Definition was still the prevalent form, although High Definition was quickly taking over.
Panasonic spotted a gap in the market and released a series of 3-CCD camcorders capable of shooting in much better quality than normal 1-CCD home camcorders.
A CCD chip from a regular camcorder
In basic terms, (mainly because this is a far as I understand it) a traditional camcorder contains 1 microchip that records the image from the lens and turns it into a digital signal.
A three chip (3-CCD) camcorder has three microchips, one for each primary colour. This means that the 3-CCD camcorder gives effectively three times the quality of a regular camcorder.
This quality isn’t broadcast standard but it very useful for greenscreen.
Greenscreen, chromakey or (in 1970s Doctor Who) Colour Separation Overlay works by having a computer recognise a single colour and removing it from an image or video. Then any other image can be used to fill in the removed bits. For this you need to provide a solid primary colour background to your presenter but problem with regular 1-CCD camcorders is that they provide a very poor signal, full of noise or rather not a single colour.
3-CCD camcorders have a chip for each primary colour so the colours are much less noisy and therefore much more solid.
Why a green backgroud?
Red is the main colour in human skin tones (certainly more than blue or green) so we don’t pick red.
Blue works best with Film so on Making-Of DVD extras you’ll often see blue as the background, but for digital video, the colour processing works best with green.
Green contains more information in the digital video signal than blue. It’s as simple as that really.
Back to cameras
Just because something says HD doesn’t mean better quality than SD. HD on camcorders refers to the output size of video not the quality of the image. Plus, lets face it HD video is bigger, so processing requires a more powerful computer and more storage space. In school we try to stick to 640×480 video compressed into WMV, so at that size there’s no point shooting anything in HD.
Unfortunately, the Panasonic 3-CCD range of camcorders we bought has now disappeared in the HD/SD battle. They were the NV-GS500 and cost around £500.
I’ve been in a bit of a minor panic about what to do when they need replacing. The market is still in flux so it’s hard to tell what the next best option will be. Right now, it seems like there is nothing near the GS500s for quality and price.
Panasonic has released a series of 3-CMOS camcorders. CMOS is the chip normally used inside digital stills cameras and is generally considered better than CCD. A camcorder called a 3MOS has three of these chips just like the 3-CCD.
In future posts, I’ll talk about how we connect the cameras to the video switcher, which also affected the decision over which camera to buy.
Ultimately, the cameras are the most important part of the studio as once a camera is chosen, everything falls into place. Video standards, vision mixing and even which tripods are all governed by that choice.