Yeah, I know that, but once the gunner has the target acquired, is it the electro optical sight that locks the target or is it the missile seeker. I'm not a Strela expert, but I doubt that it has any auto-tracking feature. Like a manpads, it is pointed towards the target over the optical sight, that is parallel with the missile, and the missile locks itself.
Nice image, where did you get it from? http://www.steelbeasts.com/Downloads/p13_sectionid/320/p13_fileid/1851
