P3P in low light vs Mavic - two videos that make me scratch my head

[theTastyCat]

Hey all - was fortunate to be directly in the middle of the eclipse path on Monday. Got some good footage but was *very* disappointed in how grainy my video of totality (similar light levels to maybe 10 minutes after sunset normally) - I had it on 800 ISO, 30 fps, and still *really* grainy. Here's my video - totality begins at 0:48.

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Now check this out - portions of this next vid I shot at 1600 ISO!! And not grainy one bit - same drone (actually I think I got a refurb back after stress cracks so possibly different drone). Granted there was probably more light in this vid. It's the second shot of the video and comes back several times:

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NOW HERE'S THE KICKER: I found this video on youtube of eclipse footage from a guy who was in the exact same town as me during the eclipse, and his footage is perfectly exposed the entire time. I messaged with him and he was flying a Mavic Pro 4k/30 with ISO set to auto.

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So here are my questions that have been driving me crazy:

1. Why was my ISO 800 footage (of a once-in-a-lifetime event) grainy when my other footage of ISO 1600 was crisp? The only differences I can think of are the ISO1600 was shot in None 0/0/0 AWB and eclipse footage was D-Cinelike -1/-1/-1 Sunny - would any of that make a difference?

2. How the heck did the Mavic Pro footage turn out so even (always the right exposure through drastically changing lighting conditions, no visible sudden change of ISO)? Does the Mavic Pro have the ability to gradually change ISO unlike my P3P that does it in big steps?

I would *really*, *really* appreciate your input here - I'm pretty disappointed that I didn't get perfect footage of such an incredible event, but I'm also really bothered *that I can't figure out why.* I would be most grateful for your wisdom!

 

[With The Birds]

The first thing I will say is that you will almost certainly be able to at least partially improve this footage in post with careful levels adjustment using your scopes.

As to the cause- I can say with confidence, correct exposure at a stop or more higher iso will always look superior to underexposure at a lower ISO. This is largely because underexposure leads to less information representing the shadow detail, you are best exposing to the right, especially in low light.

 

[theTastyCat]

Birds, thanks so much - I'm using Davinci Resolve and have never really learned how to use the vector scopes; always relied on the histogram and my eyes. It's time for me to step it up - thanks very much for the inspiration here.