Hi there,
We have filmed a few spots for cinema release before trailers. The process is not any different as you broadcast off a digital projector not 35mm film.
The first step you need to do is determine which company you will advertise with a s they determine the spec for you to deliver.
For example if you are going through screenvision fits you goto:
http://www.screenvision.com/m/advertising/production_specs/
You will see they outline very clearly what you need to deliver to them. If you have any questions call them, they all have client support reps and they can answer all your questions.
Aside from the technical specs read their rules for approved content.
Hope this helps,
Emre
www.productionpit.com
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