Cannot Change Max Upload Size in File Field From 8mb
There are three variables in php.ini that could be limiting your upload size.

Look for the following in php.ini:

memory_limit = 32M
upload_max_filesize = 10M
post_max_size = 20M


I imagine one of these is set to 8M in your case.

Also, you will most likely have to restart apache after making the change to php.ini.