What is a 3 Chip Camcorder?
A camcorder records a video signal to a magnetic videotape for viewing or playback. These units also provide image-control functions such as focus and color balance.
Using separate sensors for red, green and blue allows for better images without the need to interpolate missing RGB information. This results in a higher quality of image and lower system-development and maintenance costs.
Improved Sensitivity and Color Control
A three chip camera uses an optical splitter block to land red, green and blue image components on separate sensors – traditionally CCDs but CMOS sensors are also starting to appear. This allows each color to be read individually without the effects of pixel binning or averaging which reduces noise and artifacts.
The result is a significantly higher amount of raw color data for each channel of the video signal. For example, a standard single-chip HD camcorder with a 2.1 MP sensor only produces 1 million pixels of green pixel data. A three-chip camera with the same pixel matrix provides 2.1 million pixels of green pixel data and four times that for each of the red and blue channels.
In addition, by using dedicated image sensors for each of the colors, a three-chip camera can utilize a low-pass filter on all sensors to eliminate aliasing in the video signal. This results in better video quality with a higher level of detail across the entire picture.
The larger pixel size of a 3 chip camera allows it to capture more video data than a single-chip design. The resulting image is sharper and more detailed with greater dynamic range. This is because the three chip design uses a Bayer filter with an offset that doubles the green pixel information over the Red and Blue pixels.
Simple single-chip color cameras use a single sensor and must interpolate RGB color information from neighboring pixels. This results in artifacts and structure details being blurred. A three chip camera uses a Bayer filter with an offset, which provides more color data for each pixel so artifacts are minimized and the image is crisper.
A 3 chip camcorder supports a broad range of formats and workflows to meet the needs of professional users. XAVC Intra/Long, XDCAM Air and 12G-SDI deliver premium 4K production with fast real-world turnaround times.
Reduced Noise at High ISO
A three chip camera can produce images at a higher ISO than a single-chip camera. However, the higher ISO setting can cause image noise in the final footage.
The noise caused by high ISO settings can be reduced with noise reduction software. This software is typically included with most cameras or is available as a free plugin for Lightroom and other programs. The program reduces image noise while preserving detail.
When shooting in low light, it is common to need to increase the ISO setting on your camera. If you can’t open up the aperture any further or increase your shutter speed any longer you will need to increase your ISO setting. This can lead to the annoying artifacts of image noise.
To reduce the impact of digital image noise, one must understand what causes it. It is important to distinguish between shot noise and read noise. Avoid underexposing your photos by using a light meter and increasing the ISO setting when needed.
Reduced System Development and Maintenance Costs
For image capture applications that require high-quality color, three-chip imaging systems eliminate the need for a separate DSP-based frame grabber and H/W processor. This preprocessing allows the system to be significantly less complex, more reliable and affordable, bringing premium 4K content within reach of audiovisual productions that would have been too expensive or complex to use with older single-chip cameras.
For the camera module, a variety of combinational logic and finite state machines manage control signals and data flow to facilitate all modules working together, as well as handle user input through switches and pushbuttons. The programmable logic resources used for these are minimal, and extra Verilog modules can be added to increase functionality without affecting performance or power consumption. The low utilization of programmable logic also leaves plenty of room for adding more memory to allow for longer recording durations. The camera also supports multiple framerates and resolutions, so the design can be modified to meet a specific application’s needs with little to no risk or cost.