Nikon updated their SDK (software development kit) bringing compatibility to OS X El Capitan:
“The Camera Remote SDKs are updated to support Mac OS X 10.11 El Capitan. (Except for D40, D60, D80 and D200)
Note: This new version of SDKs have been changed some specifications from older versions.
Please be careful to replace the older version of SDK with this new version in your application.
Please refer to the documents found inside the SDK archive files.”
If you are a programmer and have created some interesting solutions/implementations with Nikon’s SDK, please contact me so I can share them on the blog.
A list of third party software solutions based on Nikon’s SDK can be found here.