Apologies for the delay in responding to your question. I just found it halfway down the forum page.
The typical range of the RealSense cameras is 1.5 m for the SR300 camera and around 4 m for the R200 camera. The R200 is the one that is most commonly used for outdoor applications. Please be aware though that the R200 is no longer supported from the latest R3 software development kit (SDK) onwards. There are advanced new RealSense cameras being released this year, including the ZR300 which is very suited to augmented reality applications such as analyzing the movement of people in the real world.
This message was posted on behalf of Intel Corporation
Did you check the information provided by MartyG? (Thanks by the way MartyG).
Let us know if you still have doubts.
you can find a ready made middleware for people counting and people tracking at www.enliteon.com.
It uses RealSense R200 for indoor and outdoor use.