By using computer vision software, the Ecosynth approach generates 3D models of landscapes using overlapping digital photos without any information about the camera position and orientation in space.
This allows us the ability to use small, consumer grade digital cameras mounted on small platforms for making observations of the 3D structure and color reflectance of landscape vegetation.
Consumer grade, off-the-shelf, point and shoot cameras
This is a high-speed (~2 fps) camera that we began using in Summer 2010 and have continued using throughout the fall data collection season with the Hexakopter platforms. The main benefits of this camera are high resolution (10 MP) and high speed in continuous shooting mode (CS) when the shutter button is left pressed.
- STATS: 180g, 10MP max. resolution, ~2 fps in CS mode
- SD4000Settings|SD4000 Camera Settings used in Ecosynth aerial work
Casio EXLIM EX-FS10
This is a small, relatively high-speed (~1.3 fps) camera that we use in groups of 2-3 to form camera arrays. The main benefits of this camera are its small size and the enclosed camera lens. We plan to try stripping down these cameras to make lighter, multi-lens arrays. This camera is also triggered in flight by keeping the shutter button pressed.
- STATS: 140g, 9MP max. resolution, ~1.3 fps in CS mode
This camera was used to collect images at a relatively slow-speed (~0.3 fps) during our initial research phase with a kite aerial photography platform. This camera is triggered in flight using modified firmware running a custom timing script for the CHDK software, which is popular among photographers using Canon cameras. This camera collected the images used for our first paper on Ecosynth.
- STATS: 230g, 7MP max. resolution, ~0.3 fps
Modified point and shoot cameras
Casio EXILIM EX-Z33 with 3-position servo mount and programmed settings
This camera system was built by a team of Computer Science and Electrical Engineering (CSEE) Seniors at UMBC over the 2009-2010 academic year for the Senior Capstone course. This system moves a camera to a series of 3 positions using a servo and fires the camera shutter at each position, moving at roughly 1 fps. A custom program also sets camera parameters (e.g., flash, ISO, etc.) by simulating button presses via a custom hardware-software connection. The purpose of building this system was to have a camera that could 'scan' the landscape, obtaining unique, oblique angles of the forest for 3D reconstruction.
- STATS: 230g, 10MP max. resolution, ~1 fps
Professional grade / Specialty cameras
Tetracam ADC Lite - lightweight near-infrared, red, green "NDVI" camera
This is a custom made light-weight camera from Tetracam, Inc. designed to record images in the green, red and near-infrared (NIR) portions of the EM spectrum. It is designed to be light and durable enough for small R.C. platform operations and its sensor has been calibrated to relate to image data collected by typical satellite systems. Recording images of vegetation in NIR makes it possible to observe traits of water moisture and distinguish between types of materials.
- STATS: 300g, 3.2MP max. resolution, ~0.3 fps