Noob to BMCC6K getting unexpected sky banding and artifacts

Hi Folks
I'm a noob to BRAW. Recently got my 6K FF and took it out on a test shoot of some scenery.
SanDisk Extreme Pro 2TB SDSSDE80-2T00
Firmware: 8.6 (I think it's a Beta - it's the latest 8.6)
Settings: CQ Q3 Open Gate, 24fps

ISO 200, Shutter 11.2 deg ('cause I didn't have an ND)
Gen5 Film to Extended Video LUT

Exposed so no Zebras were present.
Resolve Project set to YRGB Color Managed

What's odd in the footage:
1. Purple fringing. Water also has large patches of purple amongst the more normal blue-green.
2. What looks like macro-blocking
3. Sky is very banded

Might it be Q3? Or the low ISO leaving less range for the bright areas?
I wouldn't expect such extreme blemishes from these settings but perhaps that's expected?
Thanks for any help you can offer.

Here are some clips - no IS on a pretty long lens so sorry for the shake. Gyro stab took most of it out.
https://drive.google.com/drive/folders/ ... sp=sharing

Haven’t look at your shots but a few things to eliminate obvious issues.

Are you working in Resolve? Premier?
Are you looking at proxies or camera originals?
What lens did you use? What shooting stop?

Purple on high contrast like water in sun is usually a sign of chromatic aberration.
Banding is often just workflow (using proxies or low bit depth image processing)

Let’s eliminate those first.

JB

Edit. I see you mentioned resolve. Just check you’re not using proxies instead of camera originals.

Ha! It's totally the proxies. Not used to proxies looking that terrible!

Proxies can be a good choice for editing if you like to complete your edits before colour grading and rendering which naturally would use your full resolution originals.

Oh yes. I use them all the time. Just has no idea that the proxies out of the camera would be so much lower quality than those generated by Resolve.