Ever wondered how a lens is designed, where it comes from or why things are done the way they are? This new article from Lensrentals.com's Roger Cicala may answer some of those questions.
It's a great article and well worth the read, just have some time for it.
I knew that today’s lenses are all designed using computer programs, but I was surprised to find new lenses aren’t designed from scratch. Designers start with an existing lens design and modify it. Of course, a lens designer doesn’t say “this lens really sucks, let’s use it as our starting point”. They start with a good design and try to improve it.