The USB tethering for LR 6 CC was not working for this 5DSR – it cycles as if it connects then disconnects every second.
Adobe is using an old version of code from Canon – simply copy the Canon code from EOS Utility V3 to the correct location for LR to use.
(Update – on Jan 6/2016 I updated to DPP 4 and this broke the LR tether again. I had to restore from DPP 3).
Capture One: Here is a link to fix Capture One where I sourced the fix and adapted it for LR: http://www.zachardycapture.com/2015/06/21/native-canon-5dsr-tethering-in-capture-one-8-3/
Windows LR: http://www.dpreview.com/forums/thread/3861646 (about half way down the post)
Mac – Step by Step Instructions:
1) Download EOS Utility 3.2.21 (or higher) and install.
2) Right Click on LR Icon in Dock select Option > Show In Finder
3) Click on Adobe LR and Show Package Contents (as per the example on the right).
4) in Finder navigate to:
/Applications/Adobe Lightroom/Adobe Lightroom.app
Click on Adobe Lightroom.app, right click – show package contents
Click on /Contents/PlugIns/tether-canon-plugin.lrplugin right click – show package contents
Click on /Contents/PlugIns/tether-canon-app right click – show package contents
Click on /Contents/Frameworks/EDSDK.framework/Versions/A
Create a folder called “archive” and copy the contents of folder “A” to Archive as a backup in case you need to restore.
5) Now open a new Finder window and navigate to:
/Applications/Canon Utilities/EOS Utility/EU3/EOS Utility 3.app right click – show package contents
Copy the contents of folder A to the folder in step 4. (a total of 5 items).
6) Start LR, tethering should work now.
Hope this helps – its working perfectly for me.