![](/cilla/picture/8afd4187365179bb66ed3b334ce564e8da265d42b325161c323ff16711462dff.jpg)
Like sunglasses, the filter at the top filtered most of the light, so it was safe to have a look into the telescope. Without the filter, the collected light was able to spark a piece of wood.
Gauges
Like sunglasses, the filter at the top filtered most of the light, so it was safe to have a look into the telescope. Without the filter, the collected light was able to spark a piece of wood.