RAW CAMERA AND LIGHTROOM COLOUR CURVES FOR MASKS

The AI masks are a relatively recent addition to Lightroom and Adobe Camera RAW. You may not be aware of it, but Lightroom is lacking an essential feature: the ability to apply curves to the masks. Because that feature has since been added, I noticed it. Camera Raw had it already. This tutorial is applicable whether you use Lightroom or Camera RAW. In actuality, it applies to all curves in Photoshop and Lightroom. However, I do have a more thorough Photoshop instruction here.

Additionally, I provide courses on Camera Raw, Lightroom, and Curves.

MASKS’ CURVES IN THE LIGHTROOM
First, let’s look at this picture I took in Kauai, Hawaii.

Choose the Develop module and create a mask

Choose sky.

Make adjustments with exposure and Highlights to recover details in the sky.

The 5 sliders in Lightroom and Camera Raw cover 5 regions: Black, Shadows, Exposure (Midtones), Highlights and Whites.

You can also observe these regions on the histogram and actually adjust them by dragging on the histogram.

Use the curves to exert more control over any of the regions.

To brighten and darken particular tones in your image, drag up or down after clicking the picker. (To obtain an accurate curve, you must add 2 points.) See how they function first.

Let’s create a new mask for everything but the sky.

Choose Create Mask and select sky.

Click on the 3 dot menu and choose Invert, this will swap the mask. (you could also have chosen Duplicate and Invert Mask from the previous mask for the same result.)

In curves the darks are to the left, the highlights to the right. Drag up to brighten, down to darken.

Drag up in the shadow area to open up the brightness of the image.

Notice the grass is too bright.

COLOUR USE IN CURVES, COLOUR MODE FOR CURVES
Okay, now we’re getting to the meat of the instructional. Curves in Colour mode have such strength!

Colour grading is often used if you wish to give the highlights and the shadows a different colour. In Masks, Colour Grading is not an option. When used correctly, curves can accomplish everything that colour grading can.

In the curves, you will see 3 colored dots

These stand in for (R) Red, (G) Green, and (B) Blue, the primary colours. The phrase RGB colours derives from this. RGB colours add up. When all the colours are put together, they become white light, which is how the human eye perceives colour. But that information is not necessary for this.

You could be aware of a second colour mode. CMYK. (Black, Yellow, Magenta, and Cyan. K is black, but since we are concentrating on colour, all that matters is C, M, and Y.

These are referred to as Subtractive Primaries; after all the colours are subtracted, you are left with whte. They operate similarly to pigment in paint or ink. Although it’s not necessary for this tutorial, who doesn’t want a little background knowledge?

What you will find useful (and no one talks about this in photography circles). For the purpose of Lightroom (and Photoshop) Color channels: The subtractive primaries are the opposite of the additive.

Opposite of red is Cyan

Opposite of Green is Magenta

Opposite of Blue is Yellow.

Click on the blue dot to activate the blue curve.

Drag up and the sky turns blue

Drag down and it turns yellow. Yellow is the opposite of blue.

These color channels don’t affect the tonality, they only affect the colors. (Technically, some do shift the tones a little bit, but not much)

Okay, let’s get down to business and apply this.

We want to tint the sky a little orange.

Decide on the red channel. To add a little red, drag up. not excessively.

Orange is a combination or Red and Yellow.

Go to the blue channel and drag down. Now you are mixing in some yellow to get orange. Just like mixing paints.

Choose the other mask.

Now we are going to add blue to the shadows only and Orange to the highlights only

The blue channel in the shadows should be raised. To the left of the curve are the shadows.

Drag the curve to the centre by clicking on the curve’s midtones. Now, only shadows are receiving the blue addition; midtones and highlights (highlights are to the right) are not.

This is what the curve looks like

If the effect is too much, go to the top of the adjustments and you will see an Amount slider. This reduces or intensifies all the adjustments on the mask.

And here is our final. It doesn’t matter if this adjustment is to your taste or not, the point is to learn the tools so you can make your own adjustments that suit your style on your own images.