Perhaps some picture would help... Part of the confusion may be that 'top' and 'orthographic' do not mean the same thing. 'Top' just defines the direction you are looking at your scene. 'Orthographic' means there is no perspective involved. In addition, there is a difference between 'top view' and 'top camera view'.  'Top view' is an orthographic view, no perpective. This is what you see in the top left viewport. If you look at the cubes, you only see the front face and none of the side faces of any of the cubes. 'Top camera view' is what you see when you activated the top camera in the main viewport (lower right). the top camera here uses is a perspective view and cannot be made orthographic(in vue). the central cube stil looks OK -no side faces visible- but the left and right cubes  one of the side faces shows.  As was said above, this could be remedied to a degree by changing the focal length. In my top image the focal length is 35mm and in the bottom it is 200m. The bottom image is much more similar to an orthographic view, but still not perfect. So, the problem in vue is that you can get an orthographic view in the 'top view' viewport, you can set the quality higher,  but this cannot be made bigger for the render- the size of the viewport is it. You can use the top camera in the main viewport and set the render size as big as you want, but you cannot get a true orthographic view. Would be nice if e-on added the ability to render any size of any view...

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