beak bird birds branch feather Natural material nature Perching bird pets plant special tree twig unique wood abstract colorful colourful crisp detail equation formula formulas Fractal fractals high julia mandelbrot math mathematics resolution sundfractals backdrop background book collage cover inside paper papier retro rustic series tattered torn variation variations vintage worn brickwall crooked door entrance gate leaky old red red door red gate skew tilted wooden wooden gate aged boxcar decay grunge iron metal oxide oxidized paint peel peeling rust steel surface texture weathered activity alp alps boat boats dock lake mountains paddle pedal pedalo rent rental summer tourism tourist wharf