Ugh, those messy frame rates. I like my Sony α6100, but they’ve made such a mess of the frame rates. They’ve tied the 25/30 decision to a PAL/NTSC switch (and t

Ugh, those messy frame rates. I like my Sony α6100, but they’ve made such a mess of the frame rates. They’ve tied the 25/30 decision to a PAL/NTSC switch (and this fact is completely undocumented, of course), and so if I want to record at 30 or 60fps instead of 25 or 50, I have to go to NTSC, which makes it pop up an annoying “Running on NTSC” message every time I start the camera in video mode, and then to add insult to injury it’s not even 30fps but 29.97fps, which is a real nuisance in editing. (This is all when recording on the camera; I don’t know if it would be any different via HDMI capture.) But then I’ve been adding still more fun by recording audio on my laptop with a good USB microphone, and replacing the audio recorded on the camera. But the laptop’s clock runs a bit slower than the camera’s¹ so I have to stretch the computer-recorded audio by 0.003% (Audacity: Effect → Change Speed) to counter what would otherwise be about 110ms of drift per hour (3.3 frames at 30fps). Good times. — ¹ To measure rates absolutely rather than just one device to another, you need a canonical time source; internet time servers will do, so you compare what the audio device is sending with what internet time servers report over the course of a few hours to eliminate jitter. As for why you’d care, I cared so I could tune my piano more accurately. I measured the alleged 22050Hz as being about 22048.862Hz, which means it’s running at about 99.99484% of real speed. This difference amounts to −0.9 cents, which is utterly unimportant for a solo instrument, but hey, it’s the principle of the thing.