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There are some pretty good answer in your posts, but I’ll throw my two bob’s worth in. Firstly there are no photons, bullets or particles of light! Maxwellian waves represent light perfectly. The mere act of diffraction and interference proves that. The point spread function (PSF) in the case of a Newt displays Airy rings plus spikes, the PSF represents the two dimensional Fourier transform of the aperture, The spikes are the transform of the blades, the rings represent the transform of the edges of the primary mirror plus the transform of the edges of the secondary mirror and its holder etc. If the edges of your primary mirror were softened (not so sharp) you could eliminate the Airy rings. This is very difficult in your Newt but relatively simple for RF satellite dishes and antenna arrays. Modifying edge sharpness is referred to a Apodization, this can improve planetary and lunar detail The Fourier transform of a blade usually looks similar to a rotation of the blade by 90 degrees. In other words a vertical blade will put a horizontal spike on the PSF. The spikes can be reduced or decorrelated by curving the blades in various ways. This distributes the apparent energy of the spikes into faint noise which is considered less distracting by some but enjoyed by others! Although apodizing optical elements (lenses and mirrors) is difficult it is useful for tailoring the point spread function for such things as finding exoplanets. By designing a deep null in the PSF close to the main beam helps see close in objects to bright stars or finding doubles. Just to finish off the Fourier transform of a Gaussian aperture is a Gaussian PSF. This can currently be achieved in RF antennas but difficult and expensive for optics. The main beamwidth of an aperture is inversely proportional to the aperture diameter, so very large apertures are required to improve resolution. Large baseline interferometry allows RF antennas to have very fine resolution, but is extremely difficult for current optical technology.
Barry
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