I've flown lots of rockets with outboard video cameras (both down and up looking), and offer up the below as one method to fly a camera contained internal to a rocket airframe. For this project I modified a BT-80 payload tube to internally contain a Go-Pro Hero3 (and another board-camera along with a video transmitter system). The cameras are both oriented to look-out horizontally during boost. The payload section is then designed to orient itself horizontally during descent under chute so that the cameras both view the ground, as shown in the below images.
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Internal payload structure showing the Go-Pro and the additional small black board camera lens next to it (video transmit system, battery, antenna, etc. are internal, not shown).
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Payload system inserted into the BT-80 airframe. Aperture for both cameras is covered by a curved piece of plexiglass that is epoxied to outside of airframe.
Payload section as it descends under chute. Cameras are oriented down (to ground) and about 15 degrees to one side.
Given the orientation of the Go-Pro, I do have to rotate the Go-Pro video image 90 degrees (post processing in video editor) during boost to make things look right.
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