OSi supply a variety of products for use in representing height and ground relief. Available as Digital Terrain Models(DTM’s) and also LiDAR (Light Detection and Ranging) high accuracy datasets. National coverage is available for DTM data. Partial coverage is available for LiDAR data. A Contour data set consistent with our Discovery Series mapping is also available.
Digital Terrain Models (DTM’s)
Our DTM data provides a grid of regularly spaced points at 2 m or 10 m intervals that can be used by customers with other digital data and imagery to create a 3D image of the land surface. Specialist software is needed for this application.
Series 1 DTM data is available as a 10 metre DTM with an accuracy of + or – 3 metre. This was generated from 10 metre contours and Series 1 imagery captured between 2012 and 2017.
Series 2 – DTM data is available at a 2 metre or 10 metre interval and is generated from point cloud sourced from 2 different sensors, a Digital Camera Sensor and an Airborne LiDAR Sensor. The DTM was generated to a standard sufficient for production of 25cm Ortho Rectified Imagery. In the areas generated by LiDAR data the accuracy is +/- 25cm on hard, open, level surfaces. In the areas generated by data from Digital Camera data the accuracy is +/- 1.5m on hard, open, level surfaces. This data is derived from imagery captured between 2016 – 2019
OSi supply a DTM with 10 metre postings as a CSV file to use in association with your OSi Planning Pack or for other projects allowing you to represent height and ground relief. Available to match the area of your A4 or A3 Planning Packs up to 0.5 square metres. OSi Planning Packs the can be bought from our online store.
Larger Project areas are available in TXT formats for your Area of Interest in Irish Grid (IG) or Irish Transverse Mercator (ITM) projection.
National coverage at 10 metre interval can be supplied in 20km tiles in Irish Transverse Mercator (ITM) projection in TXT format.
LiDAR – Light Detection and Ranging
LiDAR data collected between 2005 and 2014 has an accuracy of + or – 25cm. It is available for selected sites as per the coverage diagram below. It can be supplied by Area of Interest in in TXT format in Irish Grid (IG) or Irish Transverse Mercator (ITM) projections.
Processed LiDAR data coverage
There are 250 tiles in the Contour data set covering the Republic of Ireland. Each tile covers a ground area of 20km x 20km, and all are available in Irish Grid (IG) or Irish Transverse Mercator (ITM) projections in vector DXF format. This data was derived from our Discovery Mapping created during the early 1990’s.
For further information or if you would like to purchase Height Data please contact our Digital Sales Department.