Prepare to Shoot the Last Solar Eclipse 

Loving your podcast show, been tuning in Like everyday

As a person who has shot wildlife with a Canon R5 and a Lumix G9, I can say that you can NOT make up the reach difference with a larger sensor. As for the iso noise/grain, there is about a two-stop advantage to FF over MFT, in my experience. I also shot with an R6 for a while, and could comfortably shoot at iso 25600, knowing I could clean it up in a post and(assuming it was a good shot to begin with) the noise/artifacts wouldn't distract from the image. On the G9(same 20mp) that comfort limit is iso 6400. THAT said... if I want 800mm of reach on the R6, I need the very large, very long min focus distance, non-weather sealed 800/11 prime. On the G9, I can use the 100-400/4-6.3 Leica which is the second smallest 100-400 zoom I know of(only the RF 100-400 is smaller and lighter, and it is f/5.6-8 and not sealed) which is also sharper and better built. Yes, it's a little more expensive, but worth it. ALSO, the 4:3 aspect means the apparent size of the subject is actually slighter larger on the G9 than even the 2x crop factor would indicate.

I think they say Earths orbit is elliptical which would mean the speed around Sun changes throughout the year