Siebren van der Werf

The effect of aperture and seeing on the visibility of sunspots when using early modern and modern telescopes of modest size

Using the convolution of seeing and diffraction, the relation between seeing and aperture in the visibility of sunspots is explored. It is shown that even telescopes with apertures smaller than 5 centimetres are significantly affected by seeing. Although larger aperture instruments suffer more from seeing than smaller ones, their level of detail always remains better under the same atmospheric conditions.