Adobe Lightroom was a pretty slick piece of software to begin with, but over the past several updates it has become an incredibly powerful tool for photographers. Of all the different controls and tools available within the software, the Detail panel has become one of my favorites. If you use Adobe Camera Raw or Adobe Photoshop, you can find the same set of controls that we're talking about today which of course is within Lightroom. Adobe has been streamlining their systems for a long enough time now that handling raw files, although from a cataloging perspective is quite different, is almost identical between Lightroom, Camera Raw, and Photoshop.
What I mean by that is that you have the same sets of controls for the image, even if they're called different things between the programs. Even though all of these examples for today are specifically talking about tools in Lightroom, the functions of the control panels should be similar enough that you can follow along in either Camera Raw or in Photoshop.
One of the things that Lightroom so brilliantly does upon file import is using the metadata to offer automated lens corrections and a default adjustment for noise reduction. When you import an image, unless you alter your import settings, Lightroom will automatically apply a basic setting for sharpening and noise reduction. This is what the software will automatically apply to your image, unless you adjust your preferences in the program to change what happens upon import.
Below we are simply comparing what the raw image looks like straight out of camera with no adjustments and what that image looks like with the Lightroom default adjustments in the Detail panel. You can see that there is some basic color noise reduction, some sharpening, and no noise reduction for luminance.
In order to harness the potential of what the Detail panel truly offers we need to understand what each of the controls is actually doing. Honestly, it took me longer than I'd like to admit to wrap my mind around what each slider is controlling, but once I bridged that gap I was able to really make the most out of every single shot. Before we delve into what the individual controls are doing, one thing that I have found to be incredibly helpful is the Alt/Option key on your keyboard. If you hold the Alt key while manipulating any of the sliders, it will display a gray image that shows which pixels are actually being modified and how much they are being manipulated as you adjust the slider. Below is a screenshot of the Alt key being held while adjusting the radius control for sharpening.
So, here is a quick breakdown of what each control in the Detail panel does.
1. Sharpening - Amount
This is exactly what it sounds like. This slider controls how intense the sharpener enacts on the image. The sharpener looks for variance between pixels and heightens the difference between them. Basically it's altering the contrast on a pixel-by-pixel basis instead of on a grouped packet of pixels, which is what the Contrast control in the Basic panel does.
2. Sharpening - Radius
The Radius controls how far from each pixel the Amount setting is allowed to affect neighboring pixels. Since the amount of sharpening is applied to standalone pixels, the radius allows that sharpening control to start to affect other pixels that are next to the pixels affected. You could think of it as a compounding effect, where the sharpening effect is allowed to expand beyond its original pixel boundaries.
3. Sharpening - Detail
The Detail slider works to preserve the details retained in the high frequency parts of the image. Instead of working on individual pixels on a standalone basis, this slider works on emphasizing the edges identified within the image. This can help you preserve the shapes and forms of grouped pixels that the software sees as an edge. You will see this effect smaller sets of shapes like strands of hair, tree bark, striations in rocks, or pretty much anything that could be seen as a connected string of similar pixels that define an edge in the image.
4. Sharpening - Masking
This slider controls how much of the image overall will be affected by the sharpening controls. If this is set to 0, then the sharpening controls will affect each and every single pixel evenly. When you start to increase the number, the masking control will start to eliminate the larger bodies of similar pixels to focus in on the smaller contrasting sets of pixels. This is where I tend to put the Alt key to use, in order to visualize which pixels are actually being affected by the sharpen settings.
5. Noise Reduction - Luminance
This slider is looking for stark luminance contrast variations between individual pixels. The higher you set the number, the more this control will start to reduce the amount of variance between the pixels, this will smooth the pixels out and reduce the amount of noise. However, the more that you reduce the luminance noise, the more you will start to lose details in the image as a whole. Finding a balance here can be tricky which is also the reason why the two subsequent sliders exist.
6. Noise Reduction - Luminance Detail
This control is to help you regain pixel contrast within the small subsets of pixels. It is looking for the smaller grouped pixels that have been smoothed over and by increasing this control it will try to increase the contrast within those small pixel packets.
7. Noise Reduction - Luminance Contrast
The Contrast slider works very similarly to the Detail slider, but instead of targeting the smaller sets of pixels, this looks to retain contrast in the larger groups of contrasting pixels. You will see the larger shapes and color sets become more defined as you increase this slider.
8. Noise Reduction - Color
This control is here to help reduce the color noise and variance between the color in the pixels. It's similar to modifying the hue and saturation controls, but on a grouped pixel-by-pixel basis. It can identify the color differences between pixels and it will look for a color in between the two to essentially even them out to become closer in color to each other. The higher you push this control, the more pixels will start to take on color similar to surrounding pixels. If you overdo it, then the pixels start to edge towards neutral hues, becoming more gray in color.
9. Noise Reduction - Color Detail
This slider will look to retain the color differences between the small sets of pixels. The higher you move the control, the more color variance will be retained. The lower you keep the control, the pixels packets will continue to look similar to surrounding pixels. I recommend sliding the control all the way to 100, just to see how intense the control really does affect your image and then scale it back to find a nice middle ground for your image.
10. Noise Reduction - Color Smoothness
This will probably not surprise you, but the Smoothness slider works very similar to the Detail slider. Instead of solely targeting the small groups of pixel sets, this control will even out the colors in a widening range when you increase the control. Setting the control at 0 means that the pixel packets will stay as they are. I like to think of this as a control for reducing splotchy areas in the image. When starting to adjust this control, you will see small groups of pixels that have similar colors. These small groups are what we see in splotchy color patterns within the image. The more you increase the control then you will start to see splotchy groups of pixels start to even out and the areas of mass within the image will attain a more uniform color. It is like expanding the radius of color similarities between grouped pixels to become larger groups of similar pixels. If done too much, then you will see patches of color disappear as they take on enough of the surrounding pixels and end up in a neutral zone.
Striking a balance between each of these controls is how you can simultaneously sharpen your image while reducing the amount of noise. It's fairly easy to spot when an image has been sharpened too much, or when it has had the noise reduced to a point where the image as a whole becomes muddled and loses too much contrast. Below is a simple before and after between what Lightroom applies to the image by default and what I have set for my images as a default preset which is applied upon import.
Above is a screenshot of the settings that I have found to work well for my files, in general. This is a Lightroom preset that I use to jumpstart my sharpening process. It's nothing fancy, but the controls that have been set up in it are exactly what you see in the screenshot, it is simply a default setup that tend to work well for my files as a blanket application for sharpening and noise reduction. I purposely set the controls for the preset to start higher than is likely necessary, by doing that I am able to gain a good grasp as to what the image is capable of and I scale back the controls as needed. Again, take the time to test the limits of the controls, find what works for your own files and your own preference, and roll with that.