There are of course exceptions with photography such as emphasizing movement or when the background it very blurred due to a shallow depth of field. As a rule I will not tilt when there are strong horizontal or vertical lines as these emphasize the tilt. On the rare occasion that I do it will be when photographing down on a subject from above (see image) or when photographing two people together with the person in the background out of focus.
To my mind, if you are shooting for an album, ultimately you will also have horizon lines in all manner of directions which to my mind gives the viewer a sense of sea sickness. I prefer to make my albums clean and design led which means constant horizontal horizons. I really do believe that it makes a huge difference.
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