1. GENERAL - Aerial photography is required to support mapping of the airports across the United States.
2. DELIVERABLES - Requirements include: near-vertical, metric quality, undeveloped, aerial photography exposed along pre-determined flight lines over airports; flight reports; photographic digital index files, ground control (if required); GPS data; camera information; and reports. An exposure test over an airport is required before the start of production. The film and data become Government property.
3. DELIVERY SCHEDULE - Exposed film will be shipped to the NOAA film processing contractor within 20 days of exposure. NOAA desires as many airports on the same roll of film as possible. A final completion date will be specified.
4. EQUIPMENT AND MATERIAL
Camera - Requirements include: single lens metric camera equal to or better than a Wild RC20/30 or Zeiss RMK-A 15/23; forward motion compensation; 9 x 9 inch format; 6 inch focal length; USGS calibration; meeting National Geodetic Survey (NGS) distortion specifications; 8 fiducial marks; and recorded information.
Film - The film used will be AGFA 200 PE, or equivalent, and will be purchased by the Contractor.
Aircraft - Equipped with camera port. Meets all FAA regulations.
5. FLYING HEIGHT - Normally 15,000 feet; departures from specified flying height shall not exceed 2 percent low or 5 percent high for all flying heights up to 12,000 feet; above 12,000 feet, departures from specified flying height shall not exceed 2 percent low or 600 feet high.
6. WEATHER, SOLAR ALTITUDE, AND TIME OF YEAR - All photography is required to show full tree leaf coverage to facilitate photogrammetric tree height determination. No clouds or cloud shadows will appear on the photographs; no photography when the ground is obscured by haze, smoke, smog, dust, or falling: snow, sleet, rain, etc.; no photography when the ground is covered by water (flood), snow, or ice; minimum visibility is 10 miles; sun angle will not be less than 30 degrees above the horizon.
7. TIDE COORDINATION - Not required.
8. NAVIGATION - The aircraft will be navigated using GPS; the cross-track flight-line deviation shall not exceed X, where X = flying height/20 (750 feet for a flying height of 15,000 feet); changes in the course of the aircraft between successive overlapping photographs within a flight line shall not exceed three (3) degrees.
9. POSITIONING OF THE AERIAL PHOTOGRAPHS - Kinematic GPS (KGPS) is not required. Stand-alone GPS or equivalent is acceptable.
10. TILT - Keep to a minimum; tilt will not exceed +/- three (3) degrees for any photographic frame; the average tilt for the entire project shall not exceed +/- one (1) degree.
11. CRAB - Compensate for crab, with a resultant error not exceeding +/- five (5) degrees, as measured from the average line of flight, and the differential between any two successive exposure will not exceed +/- five (5) degrees.
12. OVERLAP AND SIDELAP - Forward overlap will normally be 60 percent, plus 5% to minus 2% percent between consecutive exposures; sidelap will be specified, normally about 50%.
13. PHOTOGRAPH LABELING - When the camera is equipped for titling, each usable frame shall be titled per specification; sample: NOAA 06-23-99 XXP UAG332 No 2501
14. FILM SHIPMENT AND PROCESSING - The exposed film, original flight log, and raw navigation file will be shipped directly to the NOAA film processing contractor. The final digital index file, reports, and other deliverables will be sent to NGS.
15. IMAGE QUALITY - Image quality on the original negative film will meet the highest professional standards. Dark areas shall not bleed together and individual objects shall be readily discernable. Detail shall be sufficiently sharp to allow photogrammetric measurement of airport features, other fine map features, and accomplishment of other intended uses for the film. Photographic products shall also be free of abrasions, blemishes, scratches, tears, and irregularities. Fiducial marks shall be clearly visible and sharp on every negative. The camera panel of instruments and titling recorded on the film shall be clearly legible on all processed negatives.
16. EXPOSURE - Extreme care shall be exercised to ensure proper exposure; it will meet specifications for gamma and base fog density; the film exposure settings normally will be controlled from the camera's Photo Exposure Meter (PEM); for those areas where abnormal exposure objects exist, such as snow, water, etc., the PEM shall be manually overridden to produce an equivalent exposure without the abnormality; a shutter speed shall be chosen that meets the requirements of minimal image movement, at an adequate lens aperture for the prevailing lighting conditions.