# Blender – complexity inside spherical and concave cylindrical mirrors – V – a video of S-curve reflections

After some months without much Blender activities I now have some days to continue with the experiments in this series.

To get a fresh start I thought it might be funny to get a more dynamic view on the S-curve. I am going to make movies especially for the effects created by a half-sphere later on as we expect some spatial effects there. Look at the NASA movie I referred to in my first post of this series.

The images published in my last posts show that the concave part of the S-curve is the interesting one regarding reflections. The Gaussian curvature is positive there at every point. Therefore we get multiple reflections and large scale reshaping of simple regular figures or bodies. It gives us a first idea about what a half-sphere may create by the reflection of light rays.

# A movie

Below I put the video with somewhat reduced resolution but the download of the 1.5 MB may still take some time. An additional link allows you to download an mp4-file with a resolution of 1000×500 px.

Link to movie with a bit higher resolution.
mv_SC_1000_mp40001-0200.mp4

# Some remarks

All reflection patterns stem from 3 fully reflective, metallic spheres which are moved in front of the S-curves surface.
The “organic” jelly-like appearance of the pattern dynamics is partially due to the spherical form of the figures. Spherical surfaces lead to soft edges of the reflective patterns. The fully reflective surface of the spheres helps in addition.
The enlargements of some patterns during their object’s movement are due to the curvature of the S-curve in both direction, but especially along the longer symmetry axis, i.e. in the direction of the camera. This curvature increases the area from where light rays emitted from the surface of the spheres can hit the camera.
The separation and merging of some parts of the reflection patterns is due to single reflections of the spheres on fitting upper and lower parts of the S-curve. Such reflective patterns can also merge with reflective patterns emerging from central parts of the S-curve.
Multiple up/down-reflections can be seen in the beginning for the green sphere and at the end of the movie for the red sphere.

# Conclusion

Moving objects in front of the S-curve make this surface even more interesting. Again all tribute to Mr Kapoor whose S-curve object at the Kistefoss museet gave me the idea to reconstruct something similar in Blender.
Stay tuned …

Ceterum censeo: The worst living fascist and war criminal today, who must be isolated, denazified and imprisoned, is the Putler.