I recently upgraded from a Canon 6D to a Canon R5 body, and I just now discovered Fv mode. For those who don't know, there are some really useful shortcut modes for Aperture Variation, or Shutter Speed Variation (Av and Tv in Canon parlance), where I spent most of my time shooting on the 6D.
Now, with Fv mode, you can easily adjust shutter speed and aperture, as well as exposure and ISO with the flick of two dials. Once I put the camera in Fv mode, you use the top dial ("Mode" dial) to toggle from shutter speed, aperture, exposure, and ISO, then use the "Main" dial (the one on top, just behind the shutter button) to change values for each one, depending on what feature you want to adjust. You can quickly toggle between each of those things with your thumb on the "Mode" dial, then adjust the value you want to change and leave the other setting on "Auto" and let the camera decide the best setting for the shot, or you can spin the "Main" dial with your index finger, and change each of them - all without having to take your eye away from the viewfinder.
Since my 6D didn't have this, I'm finding it VERY convenient to shoot now. No more taking it into manual mode to change things for a shot, and then have to tediously change it back for the next shot. I can now make pretty much any adjust for a single shot, with my eye in the viewfinder. It's a real game-changer, and there is literally no more need for Av or Tv modes for me at all!
I was just wondering if other R-series Canon shooters stay in Fv mostly as well. I only just found out about it myself, after seeing a YouTube video on its utility. I had been using Av and Tv as I did on my old 6D, but now, there's no more need.
Anyway, just wanted to share my "Today I Learned" moment.
Cheers.