Georeferenced orthophotograph of Helsinki from 1969. The shooting has been conducted on 26th and 27th May 1969. 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 10 centimeters. The ortophotograph is in black and white.
The coordinate system of the orthophotograph is ETRS-GK25 (EPSG:3879).
The data is available as 4 different compressed TIFF/TWF files: Western Helsinki (Espoo) (478 Mb), city centre of Helsinki (517 Mb), Eastern Helsinki (Itäkeskus) (643 Mb) and Östersundom (552 Mb). Each compressed file includes an index (PDF file, 1,5 Mb) as well as aerial image as smaller TIFF photo files and TFW location files. TIFF files have a size of 10000 px * 10000 px and a terrain resolution of 10 cm.
The files have been named as follows: orto_yyyxxx_10cm.tif and the associated orto_yyyxxx_10cm.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