Glass on screenshots

[Timrath]

In some of my screenshots, glass appears translucent, exactly as it is during gameplay. But most times when I take a screenshot, glass will become opaque for a second, and appear like that in the screenshot. How can I ensure that glass stays see-through whenever I want to take a picture?

 

[Timrath]

I just made 20 screenshots with identical angle in rapid succession through a glass wall. In 19 of them, the glass was opaque; in 1 (the 16th) it was translucent. Weird...

 

[Timrath]

I found the answer myself. When you take two screenshots in VERY fast succession, the first one will always have opaque windows, while the subsequent ones will turn out with translucent windows.