To shrink an Orchestrator database log file (ldf) there is an option in SQL to shrink a database log file.
My experience is that this does not always work so the other solution is to remove the log file. Just remember to back up before doing any of the mention steps below because this solution insolvens deleting information.
Below is a picture of a ldf file from Orchestrator that is about 33Gb.
To remove the Orchestrator ldf file start off by stopping the Orchestrator services.
After the services are stopped, detach the Orchestrator database.
When this window pops up just select drop connections and click ok.
(If you are out of disk space there will be an error dialog showing up. Try to free some disk space and then detach again)
When the database is detached, delete the ldf file.
The next step is to attach the Orchestrator database again.
When this window shows up click Add and select the Orchestrator database file.
In the same window as above, remove the Orchestrator database log file by selecting it and click Remove.
Click Ok on the Attach Databases window.
When Attaching the Orchestrator database a new log file is created.
Start the Orchestrator services.