Tucked away in the corner of an optics catalog, Fergus found a special filter that blocks visible light, but not IR or UV.
费格斯在一本塞在某个角落的光学器材目录里发现了一种能阻隔可见光的滤光片。
2
The left image is taken by replacing the 28mm UVfilter with a polarizer.
左边的图像是由偏光片更换过滤器与一个28毫米的紫外线。
3
Clouds and pollution don't filter out UV rays, and they can give a false sense of protection. This "invisible sun" can cause unexpected sunburn and skin damage.