Perspective control

Digital post-processing software provides means to correct converging verticals and other distortions introduced at image capture.

Adobe Photoshop and GIMP have several "transform" options to achieve, with care, the desired control without any significant degradation in the overall image quality.

RawTherapee, a free and open-source raw converter, includes horizontal and vertical perspective correction tools too.

This effect is minor for small angles, and can be corrected by hand, manually stretching the vertical dimension until the proportions look right,[5] but is automatically done by specialized perspective transform tools.

How significant this is depends on the original image resolution, degree of manipulation, print/display size, and viewing distance, and perspective correction must be traded off against preserving high-frequency detail.

These have virtual cameras within to create the images, which normally have modifiers capable of correcting (or distorting) the perspective to the artist's taste.