Specifications include, but are not limited to: provide information to prospective vendors. The vendor will be expected by the County to generate orthoimagery for 884 square miles of Benton County. The orthoimagery imagery must meet NMAS and FEMA mapping requirements. The aerial project must be accomplished during the winter or early spring during leaf-off conditions with greater than 30° sun angle. Preferably during the months of December and January. Digital Ortho Rectified Photography a. Digital orthos shall be created from existing DEM provided by the COUNTY b. All additions and corrections by Vendor to existing DEM required to accomplish the rectification to the specified accuracy will be merged by the Vendor into the existing DEM and delivered to the COUNTY as an updated DEM. c. Digital orthos shall be delivered in Arkansas State Plane North, North American Datum 1983, United States Feet d. All data will be delivered in a Vendor derived grid system or a USGS Quad system. In this proposal we will make reference to USGS quads only to describe a grid or tile system. e. At a minimum, digital orthos shall be delivered in the following formats. In no instance should any file size be greater than 1 GB: i. Geo-tiff (projection information embedded in the tiff image header) a tfw for each image shall be supplied as well in quarter-quarter quadrangle format. ii. Mr. SID (compressed 20:1) and “world file” (sdw) for each image shall be supplied for the captured resolution of imagery. These files shall mosaic together with no seam lines and no black or no data areas without regard to layer schema or order placement of tile layers. iii. Mr. SID mosaic of the county (an sdw for each image shall be supplied as well) compressed approximately 50:1. This file shall contain no seam lines and no black or no data areas along borders.
