How Do I Take Screenshots on Halo 3?

[_KHR_]

I Know how to take screenshots on all the modes but on capaign it doesn't let me, i go onto the menu thingy where it shows the pause button, rewind, etc. and the screenshot button doesn't work i try it time and time again and it doesn't work!

Someone plz help!

 

[JDOGG1122]

try going to theater and watching yourself play then snap pictures instead of during gameplay.