Inspired by a photo from the art site Colossal (the first picture with the tennis ball.)
[url]http://www.thisiscolossal.com/2013/07/a-golden-spiral-appears-in-a-wet-tennis-ball-photographed-by-arvin-rahimzadeh/[/url]
Set the Picture slider to 0 to just play with the spiral, as a graph or a traceable point.
Choose a picture to analyze using the slider. Is it a logarithmic spiral? People are always claiming that spirals are golden spirals - logarithmic spirals with a very specific growth constant. What do you think about that?
Note: Set b to phi button puts b at that value, not literally at phi!
Other images from wikimedia via [url]http://originalbeauty.wordpress.com/2009/06/27/spirals-in-nature/[/url]
