Today’s Question: I have a Canon 1D MkIII and Canon recommends these Unsharp Mask settings as a baseline: 250% for Amount, 0.3 pixels for Radius, and a Threshold setting of 1 for low ISO settings and 4 for high ISO settings. I was hoping you could tell me how these figures translate to the details sliders in Lightroom as I would like to do all my basic editing there.
Tim’s Quick Answer: I would recommend starting values for Sharpening in Lightroom’s Develop module that are relatively subtle, and that will give you results that are somewhat similar to the settings recommended for Unsharp Mask. I would use a value for Amount in Lightroom of around 100, a value for Radius of around 0.7, and a Detail value ranging from around 10 to 25, with higher numbers being used for images with less noise and where more texture and detail are present.
More Detail: The settings for the Sharpening controls in Lightroom’s Develop module don’t provide as much latitude as the Unsharp Mask filter (or Smart Sharpen filter) in Photoshop. This is in large part because the sharpening in Lightroom’s Develop module is intended for “capture” sharpening, meaning the compensation for the slight loss of sharpness in the original capture, rather than creative sharpening or output sharpening.
The specific settings you use for sharpening will depend on your intent for that sharpening, the level of texture and detail in the image, and the resolution of the image. The settings outlined above should provide you with a good starting point as you apply sharpening to a photo in Lightroom’s Develop module.
The Amount setting relates to the strength of the sharpening effect. In other words, a higher setting for Amount produces more contrast along texture edges in the photo.
The Radius setting determines the size of the contrast “halo” effect in the photo. In other words, based on the strength of the contrast increase along texture edges in the photo, how large of an area do you want affected by that increase in contrast?
The Detail slider can be thought of as being similar to the Threshold slider in Unsharp Mask, but with a value that is in reverse. In other words, with Threshold in Unsharp Mask you are starting with sharpening that applies to all areas of texture in the photo, and increasing the value reduces the degree to which more subtle texture will be enhanced. With Lightroom’s Detail slider the higher the value the more detail you are enhancing.
Finally, the Masking slider enables you to focus the sharpening only on the highest contrast edges within the photo, versus the entire photo (or somewhere in between). A higher value focuses the sharpening on only edges that represent relatively high contrast.
It is worth noting, by the way, that with all of these sliders for the Sharpening controls in Lightroom you can hold the Alt key on Windows or the Option key on Macintosh while adjusting a slider value to see a grayscale preview of the impact of that particular setting on your sharpening effect.