As with our aerial photography, high quality is the differentiating feature of Sewall scanning and image processing. Sewall was the first company in New England to offer photogrammetric-quality scanning and digital orthophotography over a decade ago, and our expert team of imaging specialists has developed time-tested methods for scanning roll film, orthorectifying, color balancing, and mosaicking imagery. We continuously operate three Vexcel 4000HT scanners in a custom-designed, climate-controlled scanning lab, installed with a HEPA filtration system and web cam for monitoring round-the-clock.
To enhance quality, Sewall examines each individual flight line to ensure image radiometry (consistency of image brightness, coloration, and tone) throughout the project area and carefully adjusts images for consistency. During orthoproduction, each image is orthorectified and 100 percent visually inspected, and final mosaic tiles are inspected for misalignments and radiometric adherence.
Client input and involvement early in the process is key to our success. Deliverables are in georeferenced formats, uncompressed and compressed, readable in ArcGIS and AutoCAD.