New 8mp Camera?

Hey All, Hey OZ
Ive got a little question…
Ive just bought a 140/5MP cam for my 500x300 bed.
I just mount it on the laser door, at 644mm high

If i check the calculator, it says i was wrong a bought not the good cam, i should bought a 60 one.

So here the question, does the resolution would be better with a 60 then my 140 at the same place or it wont change absolutely nothing ?

Thanks for ur help !