Ceiling symmetry

It can be challenging to photograph architecture such that the horizontal and vertical lines are oriented correctly. Horizontal lines need to be parallel with the top and bottom of the frame, while vertical lines must be parallel with the left and right sides of the frame. If the camera is even slightly skewed to the subject, unattractive distortion occurs. Correctly oriented images can be taken by standing dead center on the subject and by paying strict attention to the sides of the image, making sure the camera is not inadvertently rotated even slightly. This is ceiling detail in the Salzburg Cathedral in Austria photographed with a 24mm focal length. I hand held the camera, and the settings were 1/60, f/4.0, and 3200 ISO. In post-processing, I lightened the shadows with the burn tool in Photoshop so the detail in the paintings showed nicely.