Just saw the second stage of crew-4!

[Cloakedwand72]

Just saw a faint trail of the second stage of crew-4 when they flew past Jacksonville! Curious why can’t I see the second stage plum with my naked eye but only my GoPro camera?

[monophonic]

Possibly because to increase sensitivity the GoPro is somewhat sensitive to near visible infrared light, and the plume happens to be quite bright at those wavelengths. I know this is very common with smartphone cameras; that's the reason you can see a remote control led light up bright in a phone camera but not with your eyes.

[wumpus]

6 hours ago, monophonic said:

Possibly because to increase sensitivity the GoPro is somewhat sensitive to near visible infrared light, and the plume happens to be quite bright at those wavelengths. I know this is very common with smartphone cameras; that's the reason you can see a remote control led light up bright in a phone camera but not with your eyes.

From what I understand (at least this was true ~2010ish), CMOS sensors are fully sensitive to IR light and it is only the filters placed on the lenses that makes a difference (presumably how they handle color as well).  I was building cameras for iris identification and we lit the eyes up with IR (with obvious safety considerations).  The CMOS image sensors were ordinary black and white sensors, no particular IR labeling at all (I suspect the guy who choose them had to go through a few datasheets checking that).