I came across this article over at Microsoft which, by the way has a whole slew of business articles available. Unfortunately, most don't apply to smaller operations like photo studios. This one does apply though. It discusses the opportunities companies big and small can benefit from bartering for goods and services. Here is the barter link right here.
Here are a few more places to check out for more info on the subject.
Barter Business Unlimited
International Reciprocal Trade Association
Hey, check it out, there might be a good idea just waiting for you to incorporate in your business operation.