organisation	MLURI
user_name	David Miller
user_organisation	Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen AB15 8HQ
date	09/05/96
data_set_name	Cwm Berwyn DEM 1995
data_date	1995
description	A digital elevation model (DEM) of the Cwm Berwyn study site derived by digital photogrammetry, in raster format at a resolution of 1m in X, Y and Z. The dataset is a mosaiced product from three stereo models.
raster_vector	RASTER
filename	Cb95_1mdem.img
software	Erdas Imagine 8.2, Orthomax module (developed by Vision International, a division of Autometrics Inc.).
formats	Erdas Imagine (.img), Erdas 7.5 (.lan), Arc Grid
operating_system	UNIX Solaris
format	Erdas Imagine (.img)
projection	Projection: Ordnance Survey National Grid (Modified Transverse Mercator, scale factor 0.9996, false eastings -400000, false northings 100000, central meridian 2oW 49oN).
data_quality	YES
resolution	X: 1m; Y: 1m; X: 1m.
attributes	Not Relevant
methods	Ground observations made using a Global Positioning System, in differential mode using MIDAS software. Ground observations accurate to approximately +- 1m in X, Y and Z. Observations made on 1:10 000 maps. Accuracy estimated as RMS in X, Y: 1.1m. Accuracy of Z (dependant upon benchmark observations) approximately 0.25m. Observations made on the digitized aerial photographs for interior orientation: RMS 0.26 pixel.
other	Full details of DEM accuracy available (currently on printed paper or postscript file). Photograph scale: 1:10 000; camera: Wild RC8, date of photography: 25th June 1995; Company: ADAS, Brooklands Avenue, Cambridge, CB2 2BL. Tel: 01223 455 780. Location Tywi Forest; Job Number 24/95; Film Number 650. OS 1:50 000 map number 147. Film colour negative. Colour prints were scanned by University of Joensuu, Finland. Contact Ari Talkkari. Scan resolution: 800 dpi.
copyright	Photograph copyright with ADAS and Forestry Commission. DEM Copyright ASSUMED to be MLURI.
contact	David Miller MLURI. Tel: +44 1224 318 611 Fax: +44 1224 311 556 Email: david@macaulay.ac.uk