Georeferenced orthophotograph of Helsinki from 1932. The shooting has been conducted on 23rd August 1932. The aerial photographs have been scanned into digital format and have been georeferenced with a terrain resolution of 50 centimeters.
The coordinate system of the orthophotograph is ETRS-GK25 (EPSG:3879).
The data is available as compressed TIFF/TWF file.
The compressed file (66,2 Mb) includes an index (PDF file, 5.7 Mb) as well as aerial image as 366 different compressed TIFF photo files and TFW location files. TIFF files have a size of 2000px * 2000px and a terrain resolution of 50 cm. Each image covers an area of a square kilometer.
Format of files: orto_yyyxxx_50cm.tif and the associated orto_yyyxxx_50cm.twf
yyy is the y coordinate and xxx is the x coordinate in the ETRS-GK25 coordinate system used by the City of Helsinki.