Edge fluctuation

Hello....Total Newbie here!!

DaVinci Resolve Free 16.2.7.010

I have a clip recorded from my Mavic Air 2 (1080 60fps). This is of my cleaning snow off my roof.

After rendering, I noticed that on the edge of the roof, there is a strange wavy fluctuation, especially noticeable when the aircraft is moving.

When I play the clip from the Timeline, I see it there too.

When I switch DaVinci to the "Cinema Viewer" viewer mode, I don't see the issue.

I thought it wasn't in the Source...and that is sort of true. If I view the Source at full-screen, not there. If I shrink the size of the source playback, then I can see it, although not as strongly as in Resolve.

I rendered mp4 from Resolve, and from Handbrake (using Quicktime DNxHR from Resolve). Both show the problem even at full screen.

Wondering if there are any settings which can limit this issue? I find it quite distracting and disappointing to lose my original quality.

Attached is a gif of the issue...along with my project properties.

Thanks for any help!

Interestingly, I can improve things a little bit if, on the Deliver page, I set the playback preview to 100%.

It doesn't totally fix it, but it's a little better.

Here is a gif taken from an AVI/DNxHR render, then rendered as MP4 in Handbrake.

FYI regarding the use of Handbrake...I've found my renders from Resolve to be Huge when I use settings to maintain quality, so I'm learning how to render in Handbrake which seems to maintain quality but produce much smaller files. I only have DSL internet, so file size for upload is pretty critical!

ApplicationFrameHost_nBTQnL6B9R.gif (569.14 KiB) Viewed 233 times

Many of the cheaper drones, including the Mavic Air 2 (I got the same one) are adding this stupid edge enhancement which can produce all kinds of annoying artefacts when combined with massive compression.
You have already found the right approach: export mezzanine codec and do the final encoding in HandBrake.
If you are using YouTube, you can even upload a mezzanine version if it#s not too long. They recompress anyway. Last resort might be some subtle blur.