Hi I have a new auto darkening mask from Lincoln Electric taht I paid a 100 bucks for and which uses two AA batterys and I'm not sure its auto darkening. On one side it has a small "push on" button which makes it dark, but when I am welding I am not getting that feature to happen automatically. This obviously isn't a funny issue. Is the filter side sensitive, is one side the outside and the other the inside? I cant find any info on the website...