I already know the "how to"
(iso 100, f/22, light uniform surface)
But what i wonder is why that setting?
why must be small aperture??
i thought small aperture is for lens dust?
small aperture never affect the dust which is already on the sensor itself?
but according to all the source i've been reading on internet, they all advice the same setting
amazingly, i've test with 2 different lens, same sensor dust on the 20D, so the method must be working coz the chance for 2 different lenses to have same dust pattern is 0.00...01%
anyone know why? just curious