D-Link support has helped me now, information for future buyers of DSC-935LH.
RTSP-stream:
rtsp://IP-ADRESS/play1.sdp
username: admin
password: pin-code (on label on the backside of the camera)
No answer regarding HTTP-stream or JPEG (yet). The same login doesn't work, maybe wrong syntax.
I have tried admin:pin-code@IP-ADRESS and blabla.cgi?user=admin&password=pin-code with no luck, only a blank page with the text "resultcode=unauthorized"
Update:
Works with Synology Surveillance Station 8.0 as a user-defined camera with H.264 codec (both video and sound) with another path - /play2.sdp
Second update: D-Link has informed me that HTTP-stream or JPG isn't possible on this model.