Talk:Central cylindrical projection
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Poles
[edit]Does it display the poles or are they also on infinite point?
- The poles are infinitely distant. Strebe (talk) 20:07, 27 February 2017 (UTC)
- So, it shares this property with Mercator, or is it something different? 24691358r (talk) 15:29, 3 March 2017 (UTC)
- Yes, both are cylindrical projections. In a standard projection of either type, the meridians of longitude are evenly spaced vertical lines, and the parallels of latitude are parallel horizontal lines that get spaced farther and farther apart as you approach the poles. The parallels in Mercator are adjusted back toward the equator by just the right amount to preserve angles (i.e., the angles at any point correspond to the true compass directions at that point on the globe). -- Elphion (talk) 17:40, 3 March 2017 (UTC)
Preserves scale?
[edit]What is meant by "preserves scale along vertical objects" in this edit? If the vertical objects are shown along the "meridians", the scale changes progressively; if along the "parallels" (a transverse projection), then the scale is preserved by any cylindrical projection (as the meridians are evenly spaced). -- Elphion (talk) 00:04, 3 March 2017 (UTC)
- The wording needs to be improved. Presumably the intent is, "...gives verticals the correct height for a perspective view". Strebe (talk) 17:58, 3 March 2017 (UTC)
- The thing is that in photography, a sphere is from perspective, so using a perspective projection like that essentially "undoes" the sphere conversion and produces the correct spacing. It's not like Earth, where the spherical version is the original. — Preceding unsigned comment added by 180.23.77.56 (talk) 07:58, 10 February 2018 (UTC)
- I've edited that section. WP seems not to have anything on the lenses used to make panoramas, i.e., to indicate why central cylindrical corrects the distortion. -- Elphion (talk) 19:16, 10 February 2018 (UTC)