Re: Any tips for shooting from a Cessna plane?

70mm lens or 700mm? Your typo makes it difficult for me to understand.

I do have to ask your decision making process for what I would consider an impractical shot. My first instinct, if there are resources near you, would be to pay to rent an RC camera helicopter and pay an operator. There are many small radio controlled helicopters that can handle the weight of a dSLR and afford you very dynamic shots.

I don't think filming with a 70mm lens would be terribly difficult for very short amounts of time (I've done 5-10 second shots hanging out the side of a chase car at 80mph, and I don't think a plain is much bumpier), what concerns me is that Cessna prop planes need to go about 90mph to stay safely aloft, and a 70mm lens would put you dangerously close to the ground.

If you meant a 700mm lens.. you're basically using a long lens with a doubler. The image quality goes down considerably, and most people will recommend a gyro head even on a tripod on the ground for lenses over 400-500mm for best performance.