1. GENERAL - Aerial photography is required to support mapping of the coast of the United States.
2. DELIVERABLES - Requirements include: flight planning, exposed, near-vertical, metric quality, tide-coordinated, GPS positioned, undeveloped, aerial photography exposed along pre-determined flight lines over coastline and/or coastal ports; flight reports; photographic digital index files, ground control (if required); GPS data; tide coordination data; camera information; and reports. An exposure test over a section of coastline similar to the project area is required before the start of production. The film becomes Government property.
3. DELIVERY SCHEDULE - Exposed film will be shipped to the NOAA film processing contractor within 20 days. A final completion date will be specified.
4. EQUIPMENT AND MATERIAL
CAMERA - Requirements include: single lens metric cameras (2) 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 - Two types of film: Kodak Aerocolor 3 Negative Film 2444 (9.5 inch), or equivalent, and Kodak Aerographic Black & White Infra-Red (IR) Film 2424 (9.5 inch), or equivalent; 420 and 740 nanometer filters, respectively; special care in film handling; film to be purchased by the Contractor.
AIRCRAFT - An aircraft with duall camera ports to allow simultaneous capture of color and IR exposures may be required.
5. FLYING HEIGHT - Normally between 12,000 and 25,000 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 - 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; no photography when the land-water interface is obscured by snow, ice, etc.; minimum visibility is 8miles; sun angle will not be less than 30 degrees above the horizon; sun spots (on the water) should be avoided;
7. TIDE COORDINATION - Color and IR may be required to be exposed at times corresponding with Mean High Water (MHW) and IR will be exposed at times corresponding with Mean Lower Low Water (MLLW), (the water levels for MHW and MLLW are based on an 18.6 year average).
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 - Carrier-phase, kinematic GPS (KGPS) will be used to position each exposure; the KGPS ground station will be tied to the National Spatial Reference System; the aircraft's GPS receiver must be electrically linked to the camera and have the capability to precisely time-tag the mid-point of the camera's shutter opening; the GPS antenna to camera exposure station vector must be accurately known; the datum for the horizontal positions is the North American Datum of 1983 (NAD 83); the vertical datum is the North American Vertical Datum of 1988 (NAVD 88).
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; over water or rugged terrain, an overlap of 80% will be used; sidelap will be specified, normally about 30%.
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 beach and land 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 insure proper exposure, especially with infrared film; 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.