You may need to select a Coordinate Reference System and a Viewing Projection.
The Coordinate Reference System is the means by which the Earth’s surface is mathematically transformed to appear on your screen and is the reference used to interpret and report spatial positions in datasets.
The Viewing Projection is used to present graphics on screen.
A SIS Workspace Definition (SWD) has a default coordinate system (or more precisely, both a Coordinate Reference System and a Viewing Projection).
Each SWD has a Coordinate Reference System which it remembers.
Each map window can have a different Coordinate Reference System. So you can have the same SWD displayed in several different windows, and each SWD can be displayed using a different Coordinate Reference System in each window.
If you start a SIS session, the default Coordinate Reference System is Latitude/Longitude.OGC.WGS_84. New SWDs adopt this Coordinate Reference System, but you can change it.
If you open an SWD, it uses the Coordinate Reference System it had when it was saved, but you can change it later.
Each map window can use a different Coordinate Reference System from other windows. You can select either a Viewing Projection or a Coordinate Reference System for the current window using CRS [Home-Map].
If you choose a Viewing Projection, SIS makes the Coordinate Reference System compatible with it.
If you choose a Coordinate Reference System, the Viewing Projection is made compatible.
Alternatively you can change the Coordinate Reference System, by clicking on the globe icon, located towards the right hand side of the status bar:
The following example shows some Ordnance Survey Meridian data. First it is displayed using its standard Viewing Projection (OSGB 1936.British National Grid), then using a Latitude/Longitude Coordinate Reference System:
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