@ Fred. Thank you. I need C mount, but its ok.
I generally try to create small, flexible set ups, so I try to avoid buying too much stuff.
I mean from 3,5 all the way to 12 mm. I need to be very wide I guess, but in theatre it can change.
I suspect, that with the consideation sensor size it will be at least 10,5 - 36mm and less I need to go wider, which I am not sure is possible, that should suffice once for all.
If I got right, IR coating enhances IR light in terms of visibility and contrast, so that would be nice benefit.
I am not sure how I can use back focus effectively for tracking. Having focused everything on furthest place and use the fact that lens is so wide that everything is somehow in focus?