Lenses
Lenses follows 
Smithy II in the metallurgy technology tree.
Prerequisite
Section titled “Prerequisite”Smithy II is the listed prerequisite for this technology.
Technology point cost
Section titled “Technology point cost”Unlocking Lenses costs 175 red and 20 blue technology points; no green points are listed.
Unlocks
Section titled “Unlocks”
The unlock list contains Lens and Smithy: Press. Lens is an item; this page covers the distinct technology.