Karlheinz Stockhausen music composer analogy - PSF Question

[Mustafa Umut Sarac]

German music composer Stockhausen told one time , the root of the all sounds are the few short impulses. When you compose few short notes for example din don and when you record that noise to the tape band and increase the speed , it creates a sound which we think it was unique.

I thought smallest root of the image might be the point spread function dot.

I want to ask few questions :

- First , does psf varies or changes on the photographic image or does it always the same ?
ps. I thought if the sagittal and tangential mtf changes smoothly on a image , psf might be variable , but I dont know ?

- Second , how psf dot interacts with others. Does psf dot comes on to photograph as a single dot and some distance later , another dot been placed on photograph or Do psf dots interacts with other psf dots where one on other one ?

I will ask few more questions depending your answers,

Thank you,

Mustafa Umut Sarac
Istanbul