Fountain Time Dependency

[Andy Perrin]

Nope, we are talking about Mie scattering because they are largeish. That's why it's white in visible light, same as with fog/clouds.

[Stefano]

And so why there is a difference between UV and IR? I am just curious, that's not criticism.

[Andy Perrin]

There ISN'T a (big) difference in the scattering. The difference is in the absorption (as you know). I was explaining why the white part still looks gray/white in 950nm and not dark.

[Stefano]

Ok, so if I understand, calm water appears dark in IR because of the ~976 nm peak. Water droplets or water full of bubbles scatters light like a cloud (bubbles not significantly smaller than the wavelength of the light we are seeing), but still you see a bit of difference between IR and UV (shown in the last two images).

[StephanN]

 

See my results here with the bandpass at the peak. This is probably the best that can be done without going to SWIR:

https://www.ultravio...980nm-bandpass/

 

This is definitely spooky. You've probably mentioned it in some thread, but where did you get that filter from?

[StephanN]

This is definitely spooky. You've probably mentioned it in some thread, but where did you get that filter from?

 

Think I found it, this one, right? https://www.thorlabs.com/thorproduct.cfm?partnumber=FB980-10

[Andy Perrin]

Yep, that's the one!

 

Stefano, that's right!

[Stefano]

Ok, I finally got it.