Why does mapshow TextureMap display differently to mapshow Surface?

When I use mapshow to display a geotif file as a surface it crops & offsets the image.  I need to use the 3D functionality of the 'Surface' but I want it to display the full image like a 'TextureMap'.

[Z,Z_R] = readgeoraster('E:\Test\test\Data\TIF\DEM.tif','OutputType','double');
figure(2);mapshow(Z,Z_R,'Cdata',Z,'DisplayType','Surface')
figure(1);mapshow(Z,Z_R,'Cdata',Z,'DisplayType','TextureMap')