Read Me File 3/2003

The zip file contains the following files:

*.sid - Mr Sid format compressed image file (orthoimagery tile)

*.tab - MapInfo georegistration file type

*.sdw - world file - ascii file that contains real-world tranformation information for image,
	use with ESRI products

*.aux - auxillary files used with ESRI ArcGis


00ST_*.tab, 00ST_*.map, 00ST_*.id, 00ST_*.dat - 4 MapInfo seamless table files.  Each zip file contains a
	seamless table associated with all the sid files for the geographic area included.
	The seamless tables MUST be in the same directory as the *.tab and *.sid files.
	
	
00IC*.dbf - Image catalog (ESRI).  Each zip file contains a 00IC*.dbf file associated with of all the sid
	files for the geographic area included in the zip file.  The image catalog uses a system environment variable, 
	$NYSDOP.  In order to use the image catalog, the user must set the system environment variable on their
	machine before using the ESRI software. 
	The computer system variable is set in the Control Panel > System > Environment Tab
		For Variable: type nysdop
		Value: enter the full path of the directory where the *.sdw and *.sid files reside on 
		the machine.

County image index(es) - These files serve as an index for all the image files covering the county. There is a separate 
	index for each combination of film type and resolution.  Filenames and image dates are provided. The indexes 
	are provided in ArcView shapefile and MapInfo .TAB file formats.  The naming convention is as follows:

		ccc_ss_fff_indexyy.*, where

			ccc = the 3 letter county name abbreviation
			ss = the coordinate system (SP=State Plane, U=UTM)
			fff = film type (i.e. - COL, CIR, or PAN)
			yy = the year flown

	
****************************************************************************************************

Note: 1) Geographic areas may have any of the 3 film types: 'Natural Color', 'Panchromatic' and 'Color Infrared'.
         Hence the zip files may have more than one Seamless Table and Image Catalog for each film type. 

For example-
         
	 Seamless Tables:  Natural Color  (00ST_*_*_*col.tab) 
			   Panchromatic   (00ST_*_*_*pan.tab)
			   Color Infrared (00ST_*_*_*cir.tab)

	 Image Catalog:	   Natural Color  (00IC_*_*_*col.dbf) 
			   Panchromatic   (00IC_*_*_*pan.dbf)
			   Color Infrared (00IC_*_*_*cir.dbf)

      2) Zip files for quadrangles will only include orthoimagery (*.sid) and associated
	 files for the geographic areas flown in the Annual Lot programs that have been completed.  
	 As new areas are flown, the quadrangle zip files will be updated.

For more information on using the files visit our Frequently Asked Questions and General Help Page,
http://www.nysgis.state.ny.us/gateway/mg/faq.htm