Quote Originally Posted by georg16nik View Post
Any practical knowledge outside of the common frame or the so beaten up "standard laboratory conditions"?
This has nothing to do with "standard laboratory conditions". A pH value is defined and meaningful for aqueous solutions, not for CO2 in air, regardless of how chemically experienced you try to appear.
Quote Originally Posted by georg16nik View Post
I am curious to hear how many people are aware (first hand experience) of basic stuff, like the CO2 concentration of the air inside a lens and what is necessary for H2CO3 ?
In aqueous solution, H2CO3 will form from CO2 which can turn into H3O+ + HCO3-, sometimes even into 2 H3O+ + CO32-. Absent liquid water H2CO3 won't exist, much less the other forms. In aqueous solution these forms act as an acid and you also have a measurable pH value slightly below 7.

In my country that's required learning for a simple high school degree. That's where I also learned what pH values are. Remember: if it's in wikipedia, it's probably not rocket science.