Take your laptop, a PoE switch, couple patch network cables, a 6-outlet power strip and a ladder. Tell your technician to climb up the ladder and hold the Fisheye cam to the wall while you see the live stream on your laptop screen. In our experience, nothing beats an actual test, before drilling the holes. Matter of fact, we've done this a couple times to show our potential clients the "power" and capability of a fisheye lens to cover a wide area in their premises.
I would put it lower, 8-10' if possible. At that height, you'll see everything, yes, because it's panoramic after all, but you're at a harsher angle for facial details. If you lower it, you'll get better details closer to the camera.
The other thing to consider if you do mount it higher, is to see if there is an angled mount for it. It's essentially a wedge which tilts the camera down slightly, which will eliminate some of the ceiling but get more of the area below the camera.
Pro Focus LLC | 06/30/16 03:03am
A fisheye POV is no different than a standard lens POV. If you mount any camera too high, you will have poor perspective of the subject. Now, 13ft high may be fine, if your subject will be 10ft or more away. However, beyond 10ft, a fisheye isn't going to show much detail. So I think it is even more important to mount a fisheye camera at or near eye level. Since you won't see much detail beyond 10ft away, you better have a good POV for those 10ft.