Simple Luminosity Mask

[JimFox]

Simple Luminosity Mask in Photoshop

The easiest is to Double Process a Raw image. Here are the simple steps.

1. Process the Raw Image for the Sky, and save it as such.

2. Process the Raw Image for the Ground, and save it as such.

3. Open both images in Photoshop.

4. Holding down the Shift Key, click on the Sky Image and drag it onto the Ground image.
(Holding Shift will cause the Sky layer to automatically center on the Ground Layer.

5. Select (click) on the Sky Layer.

6. Press Ctrl + Alt + 2 keys. This will create your mask, you will see the blinking outlines of it.

7. Hold down the Alt key while clicking on the Create Layer Mask Icon in the Layers Panel.
(Its the small white rectangle with a gray circle in it)

And there is your layer mask, simply increasing the Dynamic Range of your image.

From here you can flatten it and process it as you would normally do.

 

[Martín el Escocés]

Useful advice, as ever, Jim!

 

[Jeffrey]

Having a bit of rouble understanding step 6. How does PS know where the sky ends and the ground begins, to mask it properly? I've done this many many times but I created my own mask of either section and then blend appropriately.

 

[JimFox]

Hey Jeffrey,

Not sure exactly what criteria photoshop is using, but it's selecting the highlights across an image, which is actually useful if you are trying to increase the Dynamic Range of a shot.

This has been a hidden feature of Photoshop since at least CS2 as that's when I first found out about it.

An additional step that I will take is after Step 7 when you have created the layer mask, I will click on the layer mask itself and then go to the Levels adjustment and darken the blacks which makes the mask darker and then will let more of the sky through from the layer below. And I will also adjust the brightness some which will block more of the ground layer from showing through. That adjustment is done to taste, and each image is done differently.

These steps are what I do pretty much on every image I process.

After doing this, I will then save it and the flatten the layers, duplicate them. And then I will use a layer mask that usually goes along the horizon and that way I can apply some separate processing to the ground on the top layer, and the sky on the bottom layer.

Jim

 

[Jeffrey]

Jim, I've used Select/Color Range, to tell PS to select highlights, shadows, or any color, and I can control the tolerance of the selection. Every time I read about 'Luminosity Masking', it always is some automated routine of a practice I've been doing for some time. But, I am in better control of exactly the areas I want. Even after the selection is made and active, I go to Quick Mask to touch up and paint any of it out or in as I see fit, mainly using the brush tool in a variety of sizes and edge softness and opacities. Masking is crucial. And I use Quick Mask a lot with the gradient tool for fade out masks. Great for landscapers. Every time this is discussed in a thread, I always see people getting the same thing done in different ways.

 

[JimFox]

Jim, I've used Select/Color Range, to tell PS to select highlights, shadows, or any color, and I can control the tolerance of the selection. Every time I read about 'Luminosity Masking', it always is some automated routine of a practice I've been doing for some time. But, I am in better control of exactly the areas I want. Even after the selection is made and active, I go to Quick Mask to touch up and paint any of it out or in as I see fit, mainly using the brush tool in a variety of sizes and edge softness and opacities. Masking is crucial. And I use Quick Mask a lot with the gradient tool for fade out masks. Great for landscapers. Every time this is discussed in a thread, I always see people getting the same thing done in different ways.

You are right Jeffrey, there is a lot of different ways to get this done for sure. For me, I exercise my control over the automated part of it by not using it if I don't like the way it's blended. But normally it's my modifying the layer mask further that is created by the "Ctrl+Alt+2 keys, where I can darken or lighten or remove selections made in it. In this article I just wanted to keep it simple to help newer photoshop users to at least get their feet wet with layer masks and blending a light and dark image. I think for a lot of people layer masking an blending can be very intimidating, so getting them to see at its most basic level is not something to be scared of, ends up being a good step for them.

Oh, and definitely the Color Range tool is a very powerful tool, and one that should have a tutorial up in here on how to use.

Jim