This is a long-term exposure shot of a flashlight with a bare bulb (no reflector) hanging on a hook from the ceiling and pushed to circle around. The camera was on a tripod facing upwards, using a red filter. Ca. 1978
<a href="//commons.wikimedia.org/wiki/User:Kmtextor" title="User:Kmtextor">Kmtextor</a>
<span class="int-own-work" lang="en">Own work</span>