visitor's timezone sent to php

Hi

I'm looking for a script that would allow me to use the visitor's local time in a server-side application (generating an image with php). For this I'll need the visitor's local timezone, to use with server time (I wouldn't rely on visitor's computer time).
I suppose it has to be a Javascript chunk integrated in php. So far, the only way I found out about was setting a cookie, then trying to get the information from there with php.
Is there any other way?

Thanks.

 

I found an article discussing this issue here:

use-php-and-javascript-to-display-local-time/

Another option was describer here. In this case they use geographic loaction of the IP address to guess the correct localtime on the suers computer:

PHPTimeZone