Hello Frank, all altitude sundials use only the Sun’s altitude.
Since the altitude is measured on a vertical circle "movable" with the Sun, a sundial that bases its action on it has to be "movable" or to have some movable part around the vertical axis: in general the whole sundial can rotate around it. For this reason all the altitude sundials must have: 1 - many hourly curves and the gnomon that is moved on the day of observation. For example the shepherd s., the ring s., etc. 2 - many seasonal curves and the gnomon mobile. When the shadow of its extreme meets the line of the day, the position of his foot gives the hour. 3 - hourly and seasonal curves, these often straight line segments, and a fixed gnomon. For ex. the famous Portici Ham sundial. So you cannot have an altitude sundial with a single curve on which the hours are placed (that is, hourly lines reduced to points) as in analemmatic. Analemmatic are never altitude sundials, even if they are built on a vertical wall. A sundial that perhaps is close to what you have described is, for example, a shepherd s. with the cylinder surface developed on a plane, like the one in the picture. Best Gianni Ferrari
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