Tetracam’s Miniature Multiple Camera Array
Note: This unit is no longer in production.
The Mini-MCA is a lightweight, compact version of Tetracam’s MCA (Multiple Camera Array) system which it replaced. Like the MCA, Mini-MCAs are available in three models. These are identified as the Mini-MCA4, Mini-MCA6 and Mini-MCA12. The number in the model name identifies the number of cameras in the array.
Each Mini-MCA system contains 4, 6 or 12 factory-aligned multi-spectral cameras. Each camera contains a customer-specified narrow-band filter that is inserted between the lens and sensor. With each exposure, 4, 6 or 12 separate bands of visible or near-infrared radiation move through each camera’s lens and filter to form a separate monochromatic image on the camera’s sensor. The images from each camera in the array are simultaneously transferred to each camera’s compact flash memory card for later access by the user.
Analysis of the combination of multi-spectral images captured during each exposure enables Mini-MCA users to identify plant stress factors, soil types, fertilizers, or insecticides; differentiate plant species or recognize other plant, soil or chemical conditions that are, in each case, able to be identified by their unique spectral signature. Mini-MCA systems are also used to graphically illustrate vegetation indices such as NDVI that are defined by relationships of specific narrow-band wavelengths. Additional information about observed vegetation may be derived from these.
The image that is captured on each Mini-MCA sensor and stored in each camera’s flash memory is made up of 1280 x 1024 pixels (1.3 MPel). Each pixel contains 8 or 10 bits of data depending upon the file format selected by the user (i.e., 10 bit DCM lossless, 8 bit RAW, and 10 bit RAW file types).
In total, with each exposure the Mini-MCA4 captures 5.2 Megapixels (4 X 1.3 MPel) of image data on four separate sensors and passes this to four separate flash memory cards. Each card stores a separate band of radiation. The Mini-MCA6 captures 7.8 Megapixels (6 X 1.3 MPel) of image data and passes this to six separate flash memory cards. The Mini-MCA12 captures 15.6 Megapixels (12 X 1.3 MPel) of image data and passes this to twelve separate flash memory cards.
Since each image is stored with metadata that identifies ancillary information such as the GPS coordinates where the image was captured, the Mini-MCA’s standard four, six or twelve 2GB cards are able to typically store approximately 500 to 900 images per channel. Higher image counts are possible when larger compact flash memory cards are inserted into the Mini-MCA in place of the 2GB cards included with the system.
PixelWrench2, the software also included with the system, enables merging, viewing and analysis of the images captured at each exposure and conversion of the camera’s native file formats into more common formats such as BMP, JPEG, TIFF, PNG, etc.