This is something that I have found myself doing as part of my normal work flow, it doesn't always work and I am not sure it was necessary in the example I've attatched (I had a hard time finding a good image to use as an example - I don't feel comfortable posting customers photos without their permission).
These are the two different situations I find it really really helpful:
1)I am having a hard time getting the delicate tonal seperation I want "so badly"...
Even if I could do this all in the original, I find it easier to see tonal relationships in B&W, so i duplicate the image twice - keep one in rgb, convert the other to lab. Then I look at the different channels and adjust the channels with layers or curves or blend them with channel blender without regard for the color shift. Net result is to combine/blend/mask the b&w channels to make the best b&w image.
Then bring the b&w image into the original on it's own layer, change blending mode of layer to luminosity.
2)The original photo is soooo damaged that the color imformation makes it harder to work on.
Same process as above, but do restoration on b&w image. Deal with retouching of colors once detail of image is repaired. This is only worth doing on real bad photos since changing the brightness will change the color saturation and require additional work on the color - but is worth it on photos where the color damage hides the shape and makes it harder to work on the photo.
This has also been a wonderful way to help "learn" a photo, to figure out what might be the best thing to do ...
Roger
These are the two different situations I find it really really helpful:
1)I am having a hard time getting the delicate tonal seperation I want "so badly"...
Even if I could do this all in the original, I find it easier to see tonal relationships in B&W, so i duplicate the image twice - keep one in rgb, convert the other to lab. Then I look at the different channels and adjust the channels with layers or curves or blend them with channel blender without regard for the color shift. Net result is to combine/blend/mask the b&w channels to make the best b&w image.
Then bring the b&w image into the original on it's own layer, change blending mode of layer to luminosity.
2)The original photo is soooo damaged that the color imformation makes it harder to work on.
Same process as above, but do restoration on b&w image. Deal with retouching of colors once detail of image is repaired. This is only worth doing on real bad photos since changing the brightness will change the color saturation and require additional work on the color - but is worth it on photos where the color damage hides the shape and makes it harder to work on the photo.
This has also been a wonderful way to help "learn" a photo, to figure out what might be the best thing to do ...
Roger
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