As low as possible :)
The problem with 360s is that their PPF falls off very fast. It's a circle so for every an additional unit of distance (foot, meter, etc.), the FoV width increased by more than 6x. A person only 5 feet away from a 360 is already at a 30+ foot wide FoV. Compare a 360 to a regular telephoto lens from our FoV tutorial:
I'd try hard to keep the panoramic as close to the ground as possible because you cannot compensate by optically zooming out like you can with a regular camera/lens.
Let us know if we can expand.
We are considering it for warehouses where just an overview would be sufficient. There are two areas considered
Camera: Vivotek FE8171V
IPVMU Certified | 03/13/13 03:52pm
With that camera, placing it at only 10 feet, the PPF is around 2-3 (caculated).
It will probably be a bit more in reality, when you consider that a 6 foot tall person's face will only be 4 feet from the camera at its closest point. But even then, PPF only jumps to around 10-11 PPF.
Also, I'm confused about the resolution of that camera. All the documentation I can find says that it's a 3.1MP camera, and that the max resolution is 1536x1536. Does anyone know if that's accurate? My PPF calculations above are based on 1536 pixels across.
Taher, the one that is really concerning is the big warehouse with a 48 foot ceiling. It would really help to use a pendant mount, like that but probably even longer:
IPVMU Certified | 03/14/13 03:18pm
Thanks Ethan, that was giving me the weirds.
Taher, it really depends on what you are trying to get from the camera, and what is practical in this warehouse. If it is practical, and does not interfere with any warehouse operations, then you could use a very long pole mount. If you just want to see what's going on, then you may not need to hang the camera too low.
IPVMU Certified | 03/15/13 11:03pm
How does PPF math work for fisheye panoramics?
If we say FoV width is 2πr (where r is distance from the camera), how many pixels are visible across that width? It is no longer the horizontal resolution of the imager. It is an circle of pixels around the center of the imager. The diameter of THAT circle (measured in pixels?) is dependendent on height and distance from the camera and the lense properties.
As you allude to, it's actually a 3d sphere rather than a 2d circle. Using 2πr is a convenient way to approximate and it does fairly represent how badly PPF declines with a panoramic camera.
IPVMU Certified | 03/16/13 09:24pm
With all that height in the warehouse, you don't need a panoramic lens. Instead use a standard camera pointed straight down. My calculations show you only need a 75 degree lens to cover the whole floorspace and six feet up the exterior walls (if mounted at the full 48 feet - if you drop it down using a pole like john shows, you will need wider). The FD8362E costs about the same as the one you are considering and should accomplish the goal (with less storage and no need for dewarping). PPF should be approaching 30, which isn't too shabby.
IPVMU Certified | 03/16/13 09:38pm
James, that's a great solution! And the FD8362E does get wider. Their spec sheet says that camera zooms out to a 93 degree horizontal field of view so it should work great for this application.
IPVMU Certified | 03/16/13 11:12pm
OK, Didn't expect this one.
Panoramic probably isn't the solution for the small room either:
The Axis M3006-V seems to be an ideal fit.
Thanks all for the valuable insight.
I will test M3006 and M3007-P. I could switch to wall mount it if 360 is not a good idea.
I apologize for not making it clear, the dimensions mentioned below are in LxBxH
I guess you read it as HxBxL