Georeferenced orthophotograph of Helsinki from 1988. The shooting has been conducted on 3 June 1988. The flight altitude of the shoot was around 1,500 meters. The aerial photographs have been scanned into digital format and have been georeferenced with a terrain resolution of 25 centimeters. The ortophotograph is in color.
The coordinate system of the orthophotograph is ETRS-GK25 (EPSG:3879).
The data is available as compressed TIFF/TWF file.
The compressed file (727 Mb) includes an index (PDF file, 13 Mb) as well as aerial image as 360 different compressed TIFF photo files and TFW location files. TIFF files have a size of 4000px *4000px and a terrain resolution of 25 cm.
Format of files: orto_yyyxxx_25cm.tif and the associated orto_yyyxxx_25cm.twf
yyy is the y coordinate and xxx is the x coordinate in the ETRS-GK25 coordinate system used by the City of Helsinki.
Source: Blom Kartta Oy ja Helsingin kaupungin kiinteistövirasto