Celery Logs into file

Celery have specific option -f --logfile which you can use:

-f LOGFILE, --logfile=LOGFILE
                    Path to log file. If no logfile is specified, stderr
                    is used.

To get information about other options, just use celery worker --help. If just want want celery worker with logging to file, your command may look like this:

celery worker -f <filename>
python manage.py celery worker -f <filename> -> in django-celery case

There are a lot of logging options for Celery you may need:
http://docs.celeryproject.org/en/latest/userguide/tasks.html#logging