One of the most common effects on Instagram is the desaturated look that looks close to grayscale but not exactly. The reds and blues are still there but the rest of the colors are gray. This effect is used for fashion, rooftopping and all sorts of photos. An?example of this is?Jacqueline Mikuta's Instagram. In this tutorial, I'll?show you the recipe to create this look easily.
Go into the Develop module to edit the photo. Here's what our image looks like in the beginning.
The majority of this effect is the Vibrance setting. Lower the vibrance and that's it. You might have to lower the saturation too but once you've done that, you already have 90% of the effect.
Next is the clarity setting which is used for the gritty/dirty look. It emphasizes the shadows on skin and can make people look they're homeless if overapplied.
Next is to lift the shadows and blue channel. Looking at some examples such as the photos by Jacqueline Mikuta, the shadows look lifted with a blue tint. Let's work on the lifted shadows first. Go to the Tone Curve setting and drag the bottom-left node up to lift the shadows. When you do this, the contrast will drop but you can fix it by adding two nodes and creating a S-curve.
Go to the blue channel tone curves then move the bottom-left node up a tiny bit. This will lift the shadows in the blue channel to give it a blue tint.
That's all. Some people on Reddit say that you have to selectively bump up the red and orange saturation in the HSL settings but I haven't found the need to. The Vibrance adjustment naturally desaturates with the same effect.