Phantom 4: huge problem of moire

Lately I have been shooting almost daily with the Phantom 4, still mostly practicing aerial footage.
I notice gigantic problems with moire with most subjects, including buildings.
I use ND filters, so I always shoot at 1/50th shutter speed. 24 frame per seconds and encoded at the same frame rate.
Any tips for reducing the problem?

Sharpness down to -3. In fact, everything down to -3. Besides 1/50 shutter speed there's not much else you can do.

I shot some video the other day and the vibration caused crazy moire lines that made the video unusable. Not sure if the shutterspeed hit a harmonic frequency with the vibration of the blade. I didn't even see the problem on the stream to my phone, when I took it to the computer I was sad.

Interesting replies, thanks.
I believe I am down to -2 on everything. I will definitely try -3.
Harmonic frequency is a possibility. I will try to shoot a 1/40th or 1/60th to see if things improve.
Is there anything that can be done in port (I use AF)? Even though I really think that is better to solve the problem while shooting

I use the Phantom 3 Pro and I thought the sharpening was way over the top when filming trees. After I put everything at -3 it looked smooth and nice. The camera isn't REALLY 4k, so in my opinion it's only really usable as 1080p, at least for selling. Same with the Phantom 4 I suppose as the camera is pretty much the same (maybe just MORE artificial sharpening)...

I also think the DLOG mode is a bit much for the 60mbps compression to handle well (noise), so I stay away from it.

Hard to say of course if vibrations are causing the effect, but 1/40 shutter speed and -3 on contrast/sharpness would at least minimize it.

I think aerial footage can benefit from slower shutter speeds (like 1/40 or even 1/30), especially if you want to speed it up a little bit in post.

I Agree about the DLOG: I tested it for a few days, but did not like it at all.
This week end wind storm forecast here (South of England). On Monday I will do some shooting and play around with settings and shutter speed.
Let's see if I can reduce this horrible moire

Maybe some benefit from this video on what DLOG, SLOG and VLOG really are and how to use them.


https://www.youtube.com/watch?v=lsP8lpLf9XI

@ vittoriocaramazza

Moire is caused by focus being to sharp and sharpness to high. You can lower sharpness and contrast but there's nothing you can do about focus on the P4 camera. Sharpness and contrast can be add in post. On a DSLR camera moire can be controlled by defocusing the cameras slightly which cannot done on a P4 camera but again reducing sharpness will help.

Also, Vittorio, having had same problem with Inspire 1 and sometimes also Typhoon H, I can say make sure you are not looking at scaling problems. I saw some clips of mine recently that I thought were moire infested but now watching them on 4K 1:1 resolution I see that they are (in some cases) fine, and in other cases not as bad as I thought.

Don't be afraid to increase shutter speed a little over the optimum "180 degree" rule ... it's that harmonic thing mentioned .. somehow the offset makes things smoother. Best practice (when possible) do same flight multiple times with different settings.

Agree: Stay away from DLOG for general use ... very nasty when you try to grade it. My tests indicate that it seldom ends up looking as good as a "Natural" setting but with some sharpening (-2 or -3)

Thanks guys, very interesting input.
Fianally the wind storm has gone, so I will be out flying the bird and trying all the different options