That map is awesome Pete! Do you know how recent that is?
To stay on topic... Why are all of you jumping his case? I don't know many car people that tint their windows, that DON'T tint it darker than legal. I've had 2 window tint tickets, and both times I've just paid it, and left it on(obviously). I've had the car for almost 6 years, had the windows tinted as soon as I got the car, and have only gotten 2 tickets since. It's a price you pay!!
Otherwise, you can try and make an appointment with an eye doctor, and see if he can write you a prescription for the tint. Not sure if it will get you out of the ticket, as the prescription won't be written until AFTER you got the ticket.
Mark