The great Asahi Pentax Super Takumar 1.4/50mm lens has a slightly radioactive glass element near the back that contains Thorium oxide to help light pass through the lens more quickly. But over time it can cause the glass to turn yellow. It is possible to fix the yellow tint with the help of LED light. On the other hand the yellow glass creates a kind of vintage feel to images with a war yellow look. It's like a permanent golden hour filter and especially interesting for autumn landscape photography. Let's have a look at some pics I've taken while hiking near Schnaitsee, Upper Bavaria, Germany, in October 2021.