Newbie: difference between Hue, Cast, Color balance and C. Temp?

Newbie : How are these different in adjusting the colour of the pic.

Thanks

ABC
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ABC wrote:
Newbie : How are these different in adjusting the colour of the pic.

Thanks

In most photo-editing programs you can adjust the relative amounts of red,
green and blue in the image. All of the functions you mentioned do
basically the same thing, and alter the amount of R, G or B to achieve a
particular effect, and the different names refer to different ways of
making the adjustment.

Colour temperature, for example, only has two controls: soure colour
temperature and display colour temperature, and it /basically/ keeps the
green constant whilst either increasing red and decreasing blue (to make
the picture "warmer" - to look more like sunrise or sunset), or vice-versa
to make an artificial light picture look more like daylight.

I suggest you search for a good tutorial on the Internet, or find a book
in your local bookshop about using e.g. Paint Shop Pro.

Cheers,
David

ABC wrote:
Newbie : How are these different in adjusting the colour of the pic.

Thanks

In most photo-editing programs you can adjust the relative amounts of red,
green and blue in the image. All of the functions you mentioned do
basically the same thing, and alter the amount of R, G or B to achieve a
particular effect, and the different names refer to different ways of
making the adjustment.

Colour temperature, for example, only has two controls: soure colour
temperature and display colour temperature, and it /basically/ keeps the
green constant whilst either increasing red and decreasing blue (to make
the picture "warmer" - to look more like sunrise or sunset), or vice-versa
to make an artificial light picture look more like daylight.

I suggest you search for a good tutorial on the Internet, or find a book
in your local bookshop about using e.g. Paint Shop Pro.

Cheers,
David

In message ,
"David J Taylor" wrote:

In most photo-editing programs you can adjust the relative amounts of red,
green and blue in the image. All of the functions you mentioned do
basically the same thing, and alter the amount of R, G or B to achieve a
particular effect, and the different names refer to different ways of
making the adjustment.

True, except the hue. While the other just scale the RGB channels, a
hue change actually will change the colors in such a way that is
irreversible. Two different hues can become the same hue after a hue
adjustment. Hue adjustment can result in 255 in a channel that
originally had 0.
--


John P Sheehy

In message ,
"David J Taylor" wrote:

In most photo-editing programs you can adjust the relative amounts of red,
green and blue in the image. All of the functions you mentioned do
basically the same thing, and alter the amount of R, G or B to achieve a
particular effect, and the different names refer to different ways of
making the adjustment.

True, except the hue. While the other just scale the RGB channels, a
hue change actually will change the colors in such a way that is
irreversible. Two different hues can become the same hue after a hue
adjustment. Hue adjustment can result in 255 in a channel that
originally had 0.
--


John P Sheehy

wrote:
In message ,
"David J Taylor" wrote:

In most photo-editing programs you can adjust the relative amounts
of red, green and blue in the image. All of the functions you
mentioned do basically the same thing, and alter the amount of R, G
or B to achieve a particular effect, and the different names refer
to different ways of making the adjustment.

True, except the hue. While the other just scale the RGB channels, a
hue change actually will change the colors in such a way that is
irreversible. Two different hues can become the same hue after a hue
adjustment. Hue adjustment can result in 255 in a channel that
originally had 0.

I regard Hue adjustment as rotating things round a colour circle, and
therefore as something which should be reversible. Depends on which
program does the adjustment? My perception probably comes from too much
involvement in colour TV!

David

wrote:
In message ,
"David J Taylor" wrote:

In most photo-editing programs you can adjust the relative amounts
of red, green and blue in the image. All of the functions you
mentioned do basically the same thing, and alter the amount of R, G
or B to achieve a particular effect, and the different names refer
to different ways of making the adjustment.

True, except the hue. While the other just scale the RGB channels, a
hue change actually will change the colors in such a way that is
irreversible. Two different hues can become the same hue after a hue
adjustment. Hue adjustment can result in 255 in a channel that
originally had 0.

I regard Hue adjustment as rotating things round a colour circle, and
therefore as something which should be reversible. Depends on which
program does the adjustment? My perception probably comes from too much
involvement in colour TV!

David

wrote:
In message ,
"David J Taylor" wrote:

In most photo-editing programs you can adjust the relative amounts
of red, green and blue in the image. All of the functions you
mentioned do basically the same thing, and alter the amount of R, G
or B to achieve a particular effect, and the different names refer
to different ways of making the adjustment.

True, except the hue. While the other just scale the RGB channels, a
hue change actually will change the colors in such a way that is
irreversible. Two different hues can become the same hue after a hue
adjustment. Hue adjustment can result in 255 in a channel that
originally had 0.

I regard Hue adjustment as rotating things round a colour circle, and
therefore as something which should be reversible. Depends on which
program does the adjustment? My perception probably comes from too much
involvement in colour TV!

David

David J Taylor wrote:

wrote:

In message ,
"David J Taylor" wrote:


In most photo-editing programs you can adjust the relative amounts
of red, green and blue in the image. All of the functions you
mentioned do basically the same thing, and alter the amount of R, G
or B to achieve a particular effect, and the different names refer
to different ways of making the adjustment.

True, except the hue. While the other just scale the RGB channels, a
hue change actually will change the colors in such a way that is
irreversible. Two different hues can become the same hue after a hue
adjustment. Hue adjustment can result in 255 in a channel that
originally had 0.


I regard Hue adjustment as rotating things round a colour circle, and
therefore as something which should be reversible. Depends on which
program does the adjustment? My perception probably comes from too much
involvement in colour TV!


It's fully reversible in PS CS via an adjustment layer.

--

John McWilliams

David J Taylor wrote:

wrote:

In message ,
"David J Taylor" wrote:


In most photo-editing programs you can adjust the relative amounts
of red, green and blue in the image. All of the functions you
mentioned do basically the same thing, and alter the amount of R, G
or B to achieve a particular effect, and the different names refer
to different ways of making the adjustment.

True, except the hue. While the other just scale the RGB channels, a
hue change actually will change the colors in such a way that is
irreversible. Two different hues can become the same hue after a hue
adjustment. Hue adjustment can result in 255 in a channel that
originally had 0.


I regard Hue adjustment as rotating things round a colour circle, and
therefore as something which should be reversible. Depends on which
program does the adjustment? My perception probably comes from too much
involvement in colour TV!


It's fully reversible in PS CS via an adjustment layer.

--

John McWilliams