Today’s Question: Could you talk about the Detail slider [for sharpening in Lightroom Classic CC and Adobe Camera Raw]? I understand that high settings of Detail shift the sharpening to deconvolution (as opposed to sharpening like Unsharp Mask at lower settings). It would help to understand more about the difference.
Tim’s Quick Answer: The Detail slider for sharpening in Lightroom or Camera Raw controls the extent to which you are enhancing fine detail in the image. A low value will help retain smooth areas of a photo, while a high value will cause fine texture (and noise) to be enhanced.
More Detail: When you apply sharpening to an image you are enhancing contrast between neighboring pixels that already have some degree of contrast. In other words, if neighboring pixels have different values, sharpening will increase the differences between the pixel values. This results in greater contrast among those pixels, which increases perceived sharpness and texture.
Increasing the value for the Detail slider will cause contrast to be enhanced among neighboring pixels even when there is minimal difference between those pixels. For those familiar with the Unsharp Mask filter in Photoshop, the Detail slider in Lightroom or Camera Raw operates much like the Threshold slider, but in reverse. A low value for Detail is similar to a high value for Threshold, and vice versa.
In general I recommend using a relatively low setting for Detail. The default value is 25, and for most images going much higher than that can be problematic. If you are really trying to enhance fine detail, you could use a higher value for Detail, but then you would need to use a very low setting for Amount.
In concept, the sharpening in Lightroom’s Develop module and in Camera Raw is intended to compensate for softness in the original capture. That type of sharpening is often referred to as deconvolution, and is different from creative sharpening or output sharpening. Using a relatively high value for the Detail slider can certainly help enhance the sharpening effect, but it can easily lead to an image that has too much fine texture and noise.
In other words, even though the sharpening controls in Lightroom and Camera Raw don’t enable you to apply extreme sharpening, there is still a risk of negatively impacting the appearance of an image by being too aggressive with sharpening. And one of the ways sharpening can quickly become too aggressive is by using a high value for the Detail slider.