Sakari Ekko
Puolalanmäki school, Turku, Finland
EAAE Summer School Working Group (Finland)
Abstract
Photography is a good way to record the Sun´s disk. A photograph can be taken in two minutes, and only a small gap in the clouds is needed for this. Its accuracy is not affected by the movement of the Sun or human interference, unlike drawing the Sun by projection. Later, the photographs can be examined and measured at ease.
Time-lapse photography or long exposure also reveals the movement of the Sun in the sky.
In this workshop, we will analyse some Sun photographs, finding the rotation period of the Sun with help of sunspots, and possibly (weather permitting) take some photographs of the Sun´s disk. The technical aspects of this kind of photography are discussed too.
For this you will need a single-lens reflex camera, long lens or telescope/spotting scope with an adaptor for your camera, a ND 5 solar filter and a sturdy tripod. Digital single-lens reflex (DSLR) cameras are very good for the purpose, and you can use a compact digital camera too. If you use a film camera, slide film is best for classroom use, because the slides can be projected on a coordinate grid to be seen and examined by the whole student group at the same time. With a digital image, you can use a beamer for the same purpose.