The secret is to (a) shoot ProRes RAW HQ; (b) use the false color of the extraordinary Ninja V as a guide; (c) avoid the false colors bright orange and red; (d) transcode to ProRes 4444 in Apple Compressor; then (e) grade in DaVinci Resolve Studio. The shadow, midtone and highlight wheels of Final Cut Pro are unsuitable for HDR grading. Do not shoot S-Log3 4:2:2.
If on the other hand, you aren’t shooting HDR; you don’t use a Ninja V; you just shoot XAVC internally and are running into problems with overexposure, then try using the magnifier. We’ve found that zebras often escape detection with the subpar low resolution LCD of the a7s III and we can see them again with the aid of the magnifier. The downside being, that zebras cannot be adjusted while the magnifier is engaged.
If you ETTR like we do, you might also find that +3 stops isn’t always necessary. Gerald Undone prefers +1.66 stops, setting C1 to 55 for 18% gray then checking the highlights with C2 Lower Limit at 94%. But we’ve found that whole process too insane for our style of shooting.
Finally, we’re more conservative when shooting people, so using false color, a little yellow is okay in the highlights, but we wouldn’t allow the entire face to be covered in yellow.
The Daejeon Chronicles 
Hey Jon,
Why did you determine the internally recorded 10bit slog3 not suitable for HDR grading? Do you have any example footage of it not being as gradeable?
Sadly the Ninja V can’t record 120fps so internal is the only option for slow motion 😦
Hi, Jonathan. Experts are unanimous in agreeing that either RAW or RGB 4:4:4 are preferable to 4:2:2 for HDR PQ. See here: https://daejeonchronicles.com/2021/04/25/raw-power/. Perhaps more importantly, my own experience after six months of shooting, grading and uploading over 60 HDR videos to YouTube is that a7s III ProRes RAW is superior to internally recorded XAVC S-I 4:2:2. The RAW files have 25% greater resolution, a more organic noise structure and richer color than internally recorded 4K. A future firmware update will enable 4K 120fps ProRes RAW with the modestly priced Ninja V+. 😁