[throwaway821909]

I've noticed a couple of LED bulbs (one with warnings that it's non-dimmable) where the PWM (presumably) means that even when I'm not looking for it, I'll move my hand quickly to grab something and it looks like I'm in a 20fps computer game, fun novelty but it wears off. Fortunately there are plenty where I don't see this.

[jbay808]

The most jarring thing is seeing the flicker when you move your eyes. If you scan your vision past a flickering light, you'll have multiple discrete images of that light left on your retina.

Strobing can also be dangerous around rotating machinery, like a lathe, because at certain RPM the machine will appear to not be spinning.

I believe the solution is to use a buck converter with enough inductance to ensure that the current to the LED is not interrupted.

[bodhi_mind]

I get this effect when using a dimmed led headlamp in the rain. I can see the rain drop fall in discrete steps.

[jrockway]

I've definitely noticed that with my bike light. You don't notice the flickering normally, but rain makes it looks like you're playing a video game at 3fps. (I think I measured the flicker and the PWM frequency was like 400Hz, which is not quite as bad as 3fps.)