I have some footage from an action camera that has been affected by vibrations. The footage seems to have an affect that looks a bit like jelly.
Is there a word for that effect and is there anything in after fx I can use to help improve it?
They call this the rolling shutter effect.
Also known as the jello or wobble effect and is caused by the side to side motion of cameras that have the CMOS sensor.
The rolling shutter effect can be caused by:
Why does this happen?
Cameras with the CCD sensor do NOT have this problem. This sensor records the whole image at once. Thus avoiding the rolling shutter effect.
There are pros and cons for using different image sensors, however it looks like we are moving to a CMOS world.
This site below explains the differences between the sensors very nicely if you are curious.
Hope that helps
This sounds like the end result of image stabilization on heavily moving footage. There is nothing that can really be done for it. The source of the problem is that you have motion blur on the original footage thanks to the movement of the camera.
Software can track how things are moving and adjust the position of the frame such that objects remain in constant position, but that doesn't change the fact that there is motion blur in the original frame as a result of the movement. Thus, when the objects stay still, you still see the associated motion blur moving around the objects and this is what causes that "jelly" look you described.
The best way to avoid it is to use a stabilized camera or use a higher shutter speed when recording your video to limit the motion blur incurred by a moving camera. If you still capture, say, 24 frames per second, but you capture each frame in 1/1000th of a second rather than 1/30th of a second, you end up with far less motion blur, but need far more light.