Dwyerfen,
I have done some research on the matter of music copyright and although there can be significant differences with the country of origin ie USA or UK, I would have to disagree with birdcat, in essence what he has said is correct regarding it being incidental, but that would generally mean background music captured ‘incidentally’ during your shoot i.e music playing on a car radio as it drove by. However as you are specifically filming a DJ playing copyrighted music at a function (of which he probably has a licence for doing so) his licences would not include recording for further public or private broadcast, which is the purpose of your film, a demo of his offered services. In the UK we must purchase a specific licence – PRS LMP Licence, to include such music on our DVD’s (Wedding & Event films for me) which cost 8 ($12 approx) for 1 1/2 hours of music on no more than 5 DVD copies. Of course you can purchase more depending on the size of your distribution needs and the cost per copy reduces with the increase in total amount. I’m pretty sure that it would be a similar situation in the USA. However if your film is going to be broadcast via the medium of YouTube then you would (probably) not need to purchase any licence as YouTube have an agreement with the music industry in place and you are now aloud to include copyrighted music in most vidoes that you upload. Although I would suggest that you check the small print, but at the worst they would just remove the video and inform you of the reason why.
Also, I make it a point to inform my clients that if they require copyrighted music in any production that they are responsible for footing the bill prior to starting the shoot! That way they have a choice – copyrighted or royalty free.
Hope that makes things a little clearer for you.
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