On Wednesday, 20 November 2019 14:47:50 UTC, Dave Liquorice wrote:
On Wed, 20 Nov 2019 05:25:07 -0800 (PST), whisky-dave wrote:

How covert do you want to be?

Not at all specifically, it was more of the thought of being able
to
determine colour (as our eyes define it) at lower levels of
ambient
light.

That would be a really big challenge because in order to see light as
our eyes define it, that light has to be present in the light source
illuminating the objects you wish to see.

Which in the case of star or moon light it is. It's our eyes that
can't work in colour at low light levels and transition from using
the cones (colour) to rods (monochrome). Also bear in mind that the
central area of our vision is exclusively cones so if you want to see
something in low light levels don't look directly at it but 15 to 20
degress away so the image is formed on the retina where the maximum
number of rods are.

See thes colour moon lit images:

So.

as I said yuo need light of teh corect wavelenghs in order to see colour.

You can''t just shine a IR floodlight and get true colour night photos.


https://www.howhill.com/weather/view...2005&m=01&d=21

Yes the gamma has been tweaked but not the colour balance.

But this wasn't taken by a CCTV camera was it ?

I;ve seen pictures taken by the hubble that have exposure times of 20 days.





--
Cheers
Dave.