Paul;
You just answered my 2 blade vs 3 blade prop question on the cloudbase jello effect.
Since you are seeing the same thing with your two blade as I am seeing on my three blade prop then the frequency of the air coming off the prop is not the answer.
I have my strut mount as close to the wing as I can get it in order to get the mount out of the prop wash. Mounted the camera upside down and chose inverted image on the GoPro video in order to get it even closer. This reduced the jello a lot at 60 fps. I am going to go back to 30 fps to see if this location gives acceptable results.
I am thinking the tie down ring mount may be the choice. This will be a pain in the rear when tying down the plane between flights, however.
Another GoPro Camera Mount
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I kinda think it has more to do with vibration coming through the airframe and struts than it has to do with prop wash. Prop wash is a factor for sure, but the tie down ring might be far enough away from the core part of the vibration source that it's less of an issue.
Airflow is also a factor but once you get flying and have positive air pressure on the camera it should stabilize a bit.
Interestingly, I chose the Virb for it's GPS and telemetry data because I thought it would be a cool addition to the flying videos. When I played the first video back, I saw the G-force data that was logged and it showed the camera being moved around and the G-forces constantly changing adding to the jello effect.
I don't know if those G-forces are caused by airflow buffeting or vibration or both.
Airflow is also a factor but once you get flying and have positive air pressure on the camera it should stabilize a bit.
Interestingly, I chose the Virb for it's GPS and telemetry data because I thought it would be a cool addition to the flying videos. When I played the first video back, I saw the G-force data that was logged and it showed the camera being moved around and the G-forces constantly changing adding to the jello effect.
I don't know if those G-forces are caused by airflow buffeting or vibration or both.
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Finally got a chance to do a camera test flight with several takeoffs and landings using the Cloud base engineering strut mount and the GoPro running at 30 fps.
I slid the mount as far up the strut as possible by turning the GoPro upside down and inverting the image collection. I used the black "O" ring cushions in the mount.
The jello effect was minimal and only at full power upon take off.
Battery life on the GoPro still sucks, but the location high on the strut seems to have taken care of the jello.
Will take a photo next time up.
I slid the mount as far up the strut as possible by turning the GoPro upside down and inverting the image collection. I used the black "O" ring cushions in the mount.
The jello effect was minimal and only at full power upon take off.
Battery life on the GoPro still sucks, but the location high on the strut seems to have taken care of the jello.
Will take a photo next time up.
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I have a GoPro HERO4 Silver mounted high up on the wing strut of the Cessna A185F that I fly at work and the one on my Maule mounted on the right tie down ring that I posted pictures of here. There's less vibration/jello in the videos taken on the Maule but I can't be certain why. The camera is farther away from any source of vibration or buffeting coming from the engine or propeller than on the 185. There are some obvious differences such as engine power and the 3-blade prop on the 185 vs. the 2-blade prop on the Maule, but I think the 6-cylinder engine in the 185 has ess vibration than the 4-cylinder engine in the Maule. It may also have something to do with smoother air flow farther out on the Maule's wing away from the turbulence that might be present near the junction of the wing and the strut. I'm happy with the tie down ring mount on the Maule. The tie down rings near the top of the strut on the 185 aren't suitable for mounting a GoPro since they're spring loaded and flop around too much.
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Hey Tom, there could some mechanical turbulence burble between the top of the strut and the underside of the wing at that junction.
By hanging the mount upside down it's possible that the turbulence is reduced and the video quality will be better.
Also, I would bet that the left wing/strut area should be smoother than the right side due to less prop wash on that side. I've only tried the left side so have nothing to compare it to.
By hanging the mount upside down it's possible that the turbulence is reduced and the video quality will be better.
Also, I would bet that the left wing/strut area should be smoother than the right side due to less prop wash on that side. I've only tried the left side so have nothing to compare it to.
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