Replacing a narrow range of hues with a different one

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tomczak
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Joined: April 25th, 2009, 12:56 am
What is the make/model of your primary camera?: Fuji X-E2
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Replacing a narrow range of hues with a different one

Post by tomczak »

There are two similar flashlights: one magenta with a black middle section and one steel bluish. I want to recolour the magenta (but not black) to see how it would look in the steel-blue version. Looks like I'm getting rusty because I can't do it cleanly. Could someone point me in the right direction?
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Wurkkos blue.jpg
Wurkkos blue.jpg (39.12 KiB) Viewed 1171 times
Wurkkos magenta.jpg
Wurkkos magenta.jpg (69.46 KiB) Viewed 1171 times
Maciej Tomczak
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jsachs
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Joined: January 22nd, 2009, 11:03 pm

Re: Replacing a narrow range of hues with a different one

Post by jsachs »

I had the best results with Selective Color Correction - could be cleaned up a little but you should get the idea:
scc v1.jpg
scc v1.jpg (53.91 KiB) Viewed 1166 times
scc result.jpg
scc result.jpg (70.3 KiB) Viewed 1166 times
I also tried Color Curves and did a hue shift to magenta and darkened the image.

Using a mask for the flashlight would make it easier to adjust since you could alter the brightness and shift all the hues and only the masked area would be affected.
Jonathan Sachs
Digital Light & Color
tomczak
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Joined: April 25th, 2009, 12:56 am
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Re: Replacing a narrow range of hues with a different one

Post by tomczak »

Cheers for that. I used the Selective Colour Correction with just one vector and with the right weight it can capture most of the colour to correct and then darken it too. I wonder why I was spectacularly unsuccessful with Remap? I also found that matching, even approximately, the target colour is a challenge. I tried using Palette tool and guess the position of the hue/saturation on the colour wheel but found it quite hard.
Maciej Tomczak
Phototramp.com
jsachs
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Joined: January 22nd, 2009, 11:03 pm

Re: Replacing a narrow range of hues with a different one

Post by jsachs »

Remap is specific to a particular RGB color while Selective Color Correction is specific to a hue/saturation combination, ignoring brightness.

The Hue-Saturation transformation works even better:
HueSat v1.jpg
HueSat v1.jpg (109.48 KiB) Viewed 1145 times
Jonathan Sachs
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pierrelabreche
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Re: Replacing a narrow range of hues with a different one

Post by pierrelabreche »

One method is to work with hue curves :

For magenta to blue :
Wurkkos blue 2.jpg.script
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Image

Similar for blue to magenta :
Image
Attachments
Wurkkos Magenta 2.jpg
Wurkkos Magenta 2.jpg (45.31 KiB) Viewed 1131 times
Wurkkos blue 2.jpg
Wurkkos blue 2.jpg (65.13 KiB) Viewed 1131 times
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