Cockpit video camera

That video above looks like what I would expect. Fairly low outside light, which helps rendition of the cabin.

The SD card may or may not work at high bit rates. Action cams are notorious for poorly implemented code (I believe they all use drivers which Sony provide for their image sensors so all the camera maker needs to do is build the rest of the camera, and some usually crappy user interface) which doesn’t buffer the data properly, so the SD card has to handle high burst data rates. I have a 256GB SD card in my X3000 and – admittedly ~2 years ago – that cost me about £200, and it won’t do 4K (100mbps). It does HD, 50mbps. But a much slower and dirt cheap SD card will work in my phone, where the OS (android) is doing the data buffering and disk writes properly. However, as I wrote previously, 4K is not worth doing unless you need it for intermediate edit steps.

The effect of the ND filter will depend on how much light there is. In sunlight, it won’t remove the prop by a long way, on mine.

Can’t help with the sound – don’t know anything about this camera. I use a separate mp3 recorder and start it at the same time as the camera, and leave both running for the whole flight. But yes it would be nice if one could record the sound track to the camera itself.

ND filter just slows down the “shutter”. There is no shutter on “CCD” sensor cameras, so the sampling rate is reduced to collect more light, which blurs the propeller.

The tradeoff of less light is – as with all photography – (a) more blurring and (b) more sensor noise. But “action cam” footage is of such (relatively) low quality that it doesn’t matter much.

IME it never quite works, in any daylight conditions I have even flown in. But it could also be addressed with specific software. It can definitely be addressed in PP (post processing, for artefact removal); I have some software for that but it is too complicated for me.

The only way I ever found for “total” prop removal is a “prosumer” camera with a manual shutter setting, 1/80 usually does it.

Main thread on this topic.

Does the prop not reappear and disappear with rpm changes?

Not dramatically.

For sure if 1/80 works at 2400rpm then you may need 1/60 at 2200rpm.

That looks good. Low distortion too AFAICS, looking at the straight horizon.

You have the same issue I have with the whistle that I had and it just needs a notch filter to be applied in the editor. This works at a particular and constant RPM

You had poor light, hence the prop doesn’t look too bad. In bright sunlight it would be very different. Whether an ND filter can remove the prop totally depends to some extent on the camera; I have never seen it removed totally with an ND filter without producing a noisy image (but that may not be evident in a flying video).