Quote:
Originally Posted by bloodhound31
Thanks Steve, Yes, I suppose it make sense to do this in midday sun as the sun is a star, as are the others.
However, not all stars give off a white/yellow light. We see things on our earth with eyes used to seeing colours under this light as "normal". If you get away from our star by say...1500 light years, what is the true colour and what becomes the new "normal" white balance?
Baz.
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Baz,
not being anywhere near an expert but it comes down to your eyes.
Your eyes have evolved to be sensitive to a certain bandwidth of
light frequencies. Monitors try to display a picture faithfully according to
your eye's characteristic sensitivity curve....or white balance.
Emulsion film...and digital CCDS have also a curve applied to attempt
to display this same curve.
Obviously, if the end receiver is your eyeballs, stuck in front of
a monitor, and any one of the devices used to capture, detect, store,
manipulate and ultimately display it for your eyeball has a different
curve...then it will be a distorted end result.
It makes sense to capture Deep Sky as close as possible to a
generic or custom WB setting...and the easiest way is white card in
sunlight.
I hope this sorta makes sense...
Just one more thing: my ccd camera has a unique sensitivity curve which
may be way off the curve of a typical eyeball.
The easiest way to tune in or calibrate my camera's RGB curves to white
light is to calibrate it on G2V stars....they give off Sun-like light
Every high-end astro imager (count me out) has probably done a G2V
calibration of their sensor, or at least, knows the calibration settings.