Pinball Dreams Deluxe is "compressed"

[WH30224]

In Pinball Dreams Deluxe the default aspect ratio gives rise to a "vertically compressed" view of the pinball tables which is letting the pinball look like a football rather than a sphere.

When playing the game in original DosBox this phenomenon still occurs, however in a much more moderate way, i.e. the pinball looks like an ellipse the shape of which comes already very close to a real sphere.

I would rather repair this myself, if I only knew where the respective settings of Boxer are hidden.