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Aerial Photography 2007
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Ohio State-Wide Imagery Project:
CIR (Color InfraRed) What makes CIR Useful?
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- 200 mapping scale - 1 Foot Pixel Resolution
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- 1 Meter Pixel Resolution Photography
- Color Infra-Red Imagery (CIR) (Scheduled for delivery in February of 2008)
Color infrared imagery is sensitive to green, red, and near-infrared portions of the light spectrum. As such, the colors on the imagery appear un-natural, but they show information about vegetation health, water and water content, impervious surfaces for water runoff, and other information not visible to the eye. Grey-scale images can be produced from color infrared imagery. Visit the USGS web site for more information on Color Infrared Photographs.
Sample 1 - PDF file showing a sample of CIR image
Sample 2 - PDF file showing a sample of a CIR image over top of our latest color photography; the CIR image is set to 0% transparency
Sample 3 - PDF file showing a sample of CIR image over top of our latest color photography; the CIR image is set to 50% transparency
Sample 4 - PDF file showing sample of CIR image over DHL / Airborne in Wilmington, Ohio
We also have available scanned CIR imagery from 1988
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What makes CIR Imagery Useful?
Leaves of healthy, growing vegetation reflect a high level of near-infrared wavelengths and appear red on color-infrared film. Unhealthy or dormant vegetation may appear light red or a light shade of blue-green (cyan), depending on the plant's degree of good health. These color distinctions make color-infrared photographs useful in assessing the health of plants.
Water, on the other hand, absorbs near-infrared wavelengths and appears black in the image. Water with varying amounts of suspended particles appears as shades of blue. Also, near-infrared wavelengths penetrate atmospheric haze and result in clear, crisp images.
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