Is my friend going bald?

I've been telling my friend he's going bald for months and he never believed me, even after I showed him these pictures of his head. Is he actually balding or am I imagining things? He also said his hair only looked like that because it wasn't combed out but even after he combed it out there were still many see-through parts. The last pic is after he combed it out. Also, when I felt his hair, there was a clear difference in thickness between the parts that are see through and the parts that aren't. The see-through parts felt like there was way less hair in my hand vs the non see-through parts.

TLDR; is my friend going bald or am I imagining things?