There are several options when it comes to camera image sensor technologies, and the right selection has a huge impact on how the images received in the camera will appear. Many Grass Valley customers have selected their camera based on the natural appearance offered by the Grass Valley line of cameras.
The most common approach of other camera manufacturers to capturing images is using CCDs of technologies known as Frame Interline Transfer (FIT) and Interline Transfer (IT), which, in addition to capturing the image in the CCD, use a portion of the surface of the CCD to transfer the image. This use of CCDs can often add some loss of definition at the edges (aliasing) or other visible defects to the transferred image, since the electronic circuits of the camera are responsible for filling the gaps that remain between the portions of image captured by the CCD.
Grass Valley, on the other hand, believes that the best way to use CCD chips is to make the most of their surface for the actual capture of the image. In the case of the Grass Valley LDK 5000 and LDK 6000 series of high-definition cameras, each 9.2 million pixel CCD captures the total frame information and then transfers that information to an intermediate buffer device, vacating the CCD while the next frame is captured. While the image is transferred between the CCD capture area and the temporary storage buffer , a mechanical shutter (similar to those of cinema cameras) covers the sensor and allows a new video frame to be sampled (not displayed but sampled), thus ensuring a completely refreshed frame. This unique process eliminates smear-like visual defects and ensures complete image sampling on Grass Valley cameras using FT technology.
Grass Valley's image capture architecture uses a proprietary technology called Dynamic Pixel Management (DPM), which won an Emmy Award for technology and engineering in 2003 in the category "Development and Application of Subpixel Imaging Devices for Television Cameras."
DPM technology was first implemented in the Philips LDK 100 camera in the late nineties and is currently leveraged by Grass Valley's full line of LDK cameras, from the very "cost-efficient" LDK 300 to the multi-format LDK 60000 mk II WorldCam HD and in the Viper FilmStream digital cinematography camera. This allows the camera to oversample optical information on a 2/3" CCD. Each GrassValley HD DPM+ CCD contains 9.2 million pixels (1,920 horizontal and 4,320 vertical pixels). With the HD DPM+ system, the pixels are arranged in selected groups and then sampled to produce a native HD image in 1080 p (in the case of the Viper and the WorldCam), 1080 i or 720 p, without the need to convert the image digitally, which would bring the potential risk of introducing visual defects. This process, again, is unique to the Grass Valley family of cameras.
This flexibility allows Grass Valley cameras to meet the technical and pricing needs of today's customers. The LDK 5000 and 6000 use 2/3" CCDs with DPM.
For example, a production company that has very specific needs for standard definition products, but wants to protect its investment in case it needs to migrate to an HD or 24p format in the future, can buy products such as the LDK 5000 standard definition camera, and subsequently upgrade to an LDK 6000 mk WorldCam (changeable 1080 i/720 p 60) or a full upgrade to the LDK 6000 WorldCam (which supports the formats 720 P 23.98, 24, 25, 29.97, 30, 50, 59.94 and 1080 P 23.98, 24, 25, 29.97, 30 and 1080 i 50 and 59.94), with which it obtains the native support of the maximum of available formats.
Recognizing the fact that customers acquire cameras based on the quality of the images they produce, Grass Valley has spent years perfecting the renowned "digital look" of its LDK line of cameras. While most professional cameras on the market use 2/3" CCDs, the method of sampling and processing red, green, and blue images differs greatly.
While taking this unique approach to the problem of CCD image capture and processing, Grass Valley engineers worked hard to develop products that offered the best value for every investment. The architecture in question has led to the market introduction of a wide range of Grass Valley digital cameras, both for SD and HD production. During this year's NAB show in Las Vegas, Grass Valley launched the LDK 400 SD and LDK 4000 single-format HD cameras. Both meet the need for high-quality yet affordable cameras, as they don't have all the nuts and bolts of the Grass Valley LDK 500 (SD) and LDK 6000 mk II WorldCam (HD), respectively. However, these new models retain the superb optical capability offered by DPM sensors, including excellent performance in defining the edges of the image.
Customers, whether in the broadcast or professional video production markets, are looking for a quick return on camera investment, and the ability to use it in a wide variety of recording situations. Grass Valley's line of cameras was designed with these types of customers in mind.
