How to Conver “Neutral grey” layer to Curve layers

[caot38489643]

How to convert Grey“neutral grey” to two curve layers perfectly (8-bit)

[Nancy OShea]

I'm not sure I undersand the question. Can you tell us more about what you're trying to do?

[caot38489643]

Manipulating the Grey layer so one is dark and the other is lights then turning the values into a layer mask for the respective Curve. That Mean What i Think about it

[Chuck Uebele]

If I understand correctly, you want to take a grayscale image that split it onto a mask for two curves: one for shadow and one for highight.

To do that, place a neutral gray (128) layer above your grayscale layer. Change the blend more to darken, then make a stamped merged visible copy ctrl/cmd-alt/opt-shift-e. That will be the basis for your shadow mask. Turn off the visibility of that layer and change the gray layer's bend mode to lighten. The make another copy. That will be the basis for your highlight mask.

I used that technique for the creation of this image. 

 

[caot38489643]

I can't split by this way:
1. Lighten Mode: highight is mixed with shadow
2. Darken Mode: is missing

[Chuck Uebele · Accepted solution]

So here is how I did it:

The original image:

Add 50% gray layer and set it's blending mode to lighten to create the base for the lighten mask:

Make a merged visible copy ctrl/cmd-alt/opt-shift-e. Then turn that layer's visibility off and change the 50% gray layer's blend mode to darken:

Make another merged copy visible of that layer. Then add a curves layer turn on the lighten merged layer. adjust the shadow endpoint to 128 to make the 50% gray go black:

Go to channels and make a selection by ctrl/cmd clicking on the thumbnail then create a curves adjustment layer. Then turn of the lighten layer and turn on the shadow layer. Use the curves and adjust the highlight endpoint down to 128. Also add an invert adjustment layer so that the shadows are white, which will be used for the mask:

Again, go to channels and make a selection of what you have. Then create another curves layer for the shadows. Once you have the two curves layer you can turn off or delete all the layers you used to make these mask. Leave the 50% gray layer set to normal blend mode. Then you can adjust the curves to recreate the original layer:

[caot38489643]

The solution is great. I have solved my problem
Thank you very much! You are a genius

[Chuck Uebele]

Glad it worked for you.

[Stephen Marsh]

I was going to recommend using layer option blend-if sliders...