Data files are offered as LizardTech's MrSID (first generation) .sid files; file processing included image enhancement using PCI. Target compression ration was 15:1 one compressed file is roughly 3 megabytes in size.
A statewide collection of 1998 - 2001 NAPP data requires about 11.5 Gigabytes of storage space. We do not plan to distribute compressed data files by any other means (cd-rom, zip drives, portable drives, ftp download, etc)
Contact the Illinois State Library to obtain indiviual, uncompressed Illinois 1998 - 2001 DOQ data files.