'Wedding commission' = being booked as the photographer for particular a wedding.
"commission" can have several meanings but in this context it means something to be done by one person on behalf of another. Thus you commission an artist to paint a picture or a photographer to take a photo
Confused of Malvern
'The greatest fool can ask more than the wisest man can answer'
|Umbrellas by pleytime|
from An A to Z of Subjects- Week 21, U
|Glass ball on a perforated metal plate _2 by harubux|