Comparing the Smart Sharpen & Unsharp Mask Filters in Adobe Photoshop

There are tons of menu items for tools in Adobe Photoshop that were put there years ago and that have been replaced with better options. The reason Adobe keeps the old ones around is because, I’m assuming, many editors have gotten used to and enjoy using those older tools. It takes time to transition to something newer and it takes some getting used to. Not many people out there like change and when it’s thrust upon them by way of a replacement tool, there’s usually some resistance. I think Adobe likes to dangle the newer tools in front of people, just to warm them up to the idea that there’s something different and better available.

In Photoshop, there are quite a few sharpening tools. Most of these tools don’t get used all that much, but one really stands out. By the way, the current sharpening tools available are Shake Reduction, Sharpen, Sharpen Edges, Sharpen More, Smart Sharpen and Unsharp Mask. These tools can be found under the Filter > Sharpen menu item. And by the way again, the tool that really stand out is Smart Sharpen.

Menu items without three dots after the text are applied immediately without any options attached to them and the items with the three dots open up a dialog box that allows for different variables to be input for customization. As you can probably imagine, simply clicking “Sharpen” isn’t the best option for the most accurate results. I mean, there’s nothing to do other than that. How can you adjust the level of sharpening?

In today’s post, I’d like to discuss the two most popular options for sharpening an image that are currently available in Adobe Photoshop. These two options are Unsharp Mask and Smart Sharpen. While these two tools sound completely different, they’re actually very similar in many respects.

Today’s Demo Image

Since it would be silly to discuss the sharpening of photographs without having a photo to sharpen, I decided to go with a picture of a beautiful flower. There’s some good detail in this image, but really, I’ll be focusing much more on the available options for each tool, rather then the potential effects they can have on a photo.

A Summary

To make a long story short, Smart Sharpen is better than Unsharp Mask. All of the features available in Unsharp Mask are available in Smart Sharpen and believe it or not, Unsharp Mask was initially created to deal with scanned images rather than digital photos. Since the developers of the Unsharp Mask tool didn’t have today’s style of photography in mind when they created it, they made a new tool that better handled what almost every photographer on the planet creates today – digital photographs.

You’ll notice that Smart Sharpen offers different types of sharpening. One of these types is called Gaussian Blur. When using this mode, Smart Sharpen is an exact duplicate of Unsharp Mask. The beautiful thing is that the Smart Sharpen tool also offers to reduce Lens Blur and Motion Blur, which is much more fitting for today’s environment. It also offers some advanced options, which I’ll discuss below.

Finally, as I’ve said a million times, it’s important to convert any layer you’re sharpening into a Smart Object. I won’t mention that below, but just be aware that this is what is supposed to happen.

Unsharp Mask

I’d like to kick things off by taking a quick look at the Unsharp Mask Tool. To access this tool, I’ll visit the Filter > Sharpen > Unsharp Mask menu item up top.

When I click that menu item, the Unsharp Mask dialog box appears, which contains three different and relatively straightforward options.

As you can see from the above screenshot, these three options are Amount, Radius and Threshold. Before I get into what each one of these options does, I think some background on sharpening in general is in order.

Here’s a question for you. Can you sharpen an image that’s a completely solid color? The answer is no, because there are no edges to sharpen. When Photoshop or any other digital image editing program sharpens an image, all it does is merely add contrast to any edge it detects in that image. If you’re not aware of what “adding contrast” is, it’s simply making brights brighter and darks darker. So, if you’d like to add some sharpening to an image with some edges in it, all Photoshop does is look for those edges and create definition in those areas. If you think about it, if Photoshop removed contrast in the area of the edges, the image would look more blurred or less defined. But since it’s adding contrast, the image appears more sharp. It’s not actually more sharp, it just appears more sharp. Within each of the sharpening dialog boxes, we’re given the option of customizing how much definition and contrast is added to the edges and where it’s applied.

Now, let’s talk about those options.

Amount: This slider can be considered somewhat like the volume control on a stereo. It turns up or down the amount of contrast that’s added or removed from any edge that’s being affected. It makes the darks darker and the lights lighter in an effort to add sharpness.

Radius: This setting is image resolution dependent and is usually kept between the values of 1 and 2. It tells Photoshop how far to reach when it’s applying the Amount of sharpening. It basically either tightens or loosens up the contrast along an edge in a photo. Adding a higher value for this setting will tell Photoshop to look beyond the normal one or two pixels and to add contrast to more and more pixels further away from the edge. With lower resolution images, you can keep this value lower and with higher resolution images, you can push this value higher.

Threshold: This setting controls how Photoshop looks at an edge or what it considers an edge. A lower threshold says that everything should be sharpened, even slight variations in solid colors or areas. A higher threshold value says that those solid areas should be ignored and that Photoshop should only consider those areas that truly have edges in them. Essentially, we have the ability to raise the threshold of what should be sharpened.

Smart Sharpen

As you can see, the Unsharp Mask tool is relatively simple. It does what it does and it does it well. The issue is, sometimes editors have different requirements and different needs. Luckily, there’s a tool to handle just about any need an editor has.

To launch the Smart Sharpen palette, I’ll head up to the Filter > Sharpen > Smart Sharpen menu item and click.

When I do that, the Smart Sharpen palette opens right up.

As you can see from the above screenshot, there are quite a few more options in this palette. At first glance, you can see that there’s a drop-down box that offers a few different types of sharpening. Or, I should rather say, sharpening for different types of blurs in images. At the time of this post, the three sharpening options include Gaussian Blur, Lens Blur and Motion Blur. I do a pretty decent job of describing these types of blurs in the following post.

The 3 Best Ways to Sharpen Photos in Adobe Photoshop

The part you’ll be looking for is down towards the bottom.

Another thing you’ll notice in this palette is that the Threshold slider doesn’t exist under the Radius slider anymore. In this tool, the Threshold slider has been replaced by much more versatile and accurate Shadows and Highlights sections. Inside of these sections are Fade Amount, Tonal Width and Radius sliders. I’ll explain what these sliders do below.

Fade Amount: This slider sets the amount of sharpening that happens in either the shadows or highlights of an image. This is a much more fine tuned control than the Amount slider in the above section, but it can be compared to that.

Tonal Width: This setting controls what’s actually a shadow or a highlight. All shadows aren’t considered simply a shadow and the same is true for the highlights. You have to tell Photoshop what you’d like adjusted. Moving these sliders to the left or to the right decreased or increases these settings. This setting controls the range of tones for the shadows and the highlights in an image.

Radius: This setting controls how much area around a pixel of either a highlight or a shadow that should be considered when determining what should be included when the adjustment is made. Moving the sliders to the left and the right will shrink or enlarge that area, respectively.

Finally, there’s a Reduce Noise slider in this palette that can help tremendously when it comes to sharpening an image. When sharpening, noise can rear its ugly head because of all the pixel adjustments taking place. You’ll need to experiment with this slider to see the effects it can have on an image, but really, I’m not sure you should be sharpening to such an extent that you’d need to remove any of the noise that may be created by over sharpening.

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I hope I gave you a clear comparison between the Unsharp Mask filter and the Smart Sharpen Filter in Adobe Photoshop. As you can see, the Smart Sharpen option has many more features, but if you’re into quickly getting a job done, perhaps the Unsharp Mask would fit your needs. If you have any questions regarding this post, please let me know in the comment section down below. Thanks for reading!