Permission level in apache

I am developing a website for my department. I am using temporary server apache in Ubuntu. I am getting a trouble in accessing files from folder. I have a situation like , I will upload a photo and it will store in the folder /var/www/web/uploads and its path is stored in mysql php database. I have no problem in saving the path in database and inside the above folder, but when i try to display in website I am not getting access to it. Its says I am not owner. Its shows www-data as a owner. I know I should be changing the permission level in terminal. I tried maximum but i am not getting fruitful results. Can any one help me how to change its permission level.