Here, using photoshop, I have overlayed the line image export from sketchup on top of the render. The verticals remain but the scale and position are not the same. One of the great features of skecthup is that all the image exports from a scene will have the exact composition. What you see is what you get
See below with sketchy edge overlay - there is a slight variation to chair feet and sketchy edge - this may be the edge lines interperatation of foot shadow