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photo:sunburst

creating sunstars and sunburst rays of light in your photos

see also:

    • When diffraction occurs around an edge like an aperture blade, it creates two visible spikes of light 180° apart and perpendicular to the blade edge
    • On a lens with an even number of blades, the diffraction spikes from opposite sides of the aperture overlap. So n-number of even blades yields n-spikes.
    • With an odd number of blades, there is no overlap. N-number of odd blades yields 2n spikes.
    • Newtonian telescopes give diffraction spikes from stars as a result of the struts holding the secondary mirror in place
    • a circular aperture does not give a sunstar pattern but creates an Airy Disk - a bright circular spot surrounded by concentric circles that represent areas of constructive and destructive interference

introduction

  • when photographing a scene with a bright light source in the scene such as the sun, or street light, many people like to shoot it with rays of light coming from it
  • this is best achieved with:
    • apertures f/11-22 (but remember as you stop down, although you get more defined rays of light, diffraction effects will reduce your image detail and sharpness)
    • use a lens with a 9-bladed diaphragm (odd numbers are best)
    • consider partly obscuring the light source
  • see also:
photo/sunburst.txt · Last modified: 2018/05/20 07:01 by gary1