By now, you probably know how to adjust simple
properties in your images, like shadows, highlights, and color. But what if you had something with
a less obvious issue; for example, a photo that looked “soft,” or maybe even a little
grainy? Fortunately, Photoshop comes with a number
of filters that can help you with something like this. Today, I’m going to show you two
of them: sharpening, and also a feature called noise reduction. Sharpening does exactly what you would think.
It can make your images sharper or clearer, so certain details are easier to see. It can’t
fix photos that are blurry or out of focus, unfortunately—but if you have an image that’s
a bit soft like this one, it can help. Any time you’re working with filters, it’s
a good idea to duplicate your layer first, so you aren’t making changes to the original.
Just right-click… choose Duplicate Layer from the menu… and then give it a name.
We’ll type Sharpened to make it easy to tell the layers apart. When you’re done, go up to Filter on the menu
bar… then mouse over the option that says Sharpen. Here you’ll find a few different filters to
choose from. They’ll all sharpen your image, but in different ways and to different degrees.
We’re going to use the one called Unsharp Mask, which may sound a bit weird, but it’s
exactly what we need. It’s very easy to use, and it’ll let us customize the results. As you can see, this filter gives you three
different settings to work with: Amount, Radius, and Threshold. You’ll see a preview in the
document window as long as this box stays checked. You also have a smaller preview that you can
easily reposition. Notice that when you hold this with your mouse, it toggles the preview
on & off, which makes it easy to compare the sharpened version to the original. Now, any time you use sharpening, it’s important
not to make any extreme adjustments—you can end up doing more harm than good. That’s
being said, it’s still OK to experiment, and nothing in Photoshop is permanent. Why don’t
we get started with the Radius setting? Radius controls the size of the details that
are being sharpened, so generally, it’s best to set it to a lower value. Too high, and
the edges will start to look unnatural or exaggerated—this is called a halo effect.
We recommend something between .3 and .5 for most images; you can even enter the exact
value here. You could go a bit higher if you were working with a higher resolution photo. The Amount setting controls the level of sharpness
being added. How much you need depends on several different things, including the image
size, so it’s good to play around with this. This time, if you go too low, the effect on
the image may not be strong enough—see how it still looks kind of soft? In this case,
I think I’m going to set the amount fairly high, somewhere between 180 and 190. Finally, sharpening has a tendency to make
image noise more visible. Those are the tiny little flecks that can make your photo look
grainy (you might even see some in the background here). Increasing the Threshold can help you
reduce this, but you have to be careful—it can cause your sharpening to become inconsistent.
Therefore, we recommend leaving this set to 0, unless the filter is creating lots of extra
noise for you. So there we have it—I think we’re done!
The difference is subtle, but it does make the image look a bit more crisp. Once again,
you can click & hold the preview to toggle it on or off. When you’re satisfied, go ahead
and click OK. Noise isn’t just caused by sharpening—it
can also appear in your image for other reasons; for example, if the photo was taken in lower
light. Luckily, you can reduce this using a noise reduction filter. Once again, you’ll start by duplicating your
layer, so you aren’t making changes to the original. You can right-click like before,
or just drag the layer down to the New Layer button. Next, go ahead to the Filter menu… then
mouse over the Noise option. You’ll want to choose the one that says Reduce Noise… and
a dialog box will appear. When you apply noise reduction, you’re actually
removing information from the image, so you have to be careful when using this feature.
Removing too much noise can lead to blurriness or a loss of detail. The key is to take it
one setting at a time, and just keep adjusting them until you’re happy with the results.
So let’s go ahead and get started. First we have Strength, which basically controls
how much noise reduction is being applied. We recommend starting at the maximum value
so you can see your adjustments more easily—but you can always set it to something lower later
if you need to. Next we have Preserve Details, which controls
how much of the original image is left untouched. You might want to play with this one a bit
while you keep an eye on the preview. Choose a setting that’s too high, and you’ll actually
cancel the effects of the filter… but if you go too low, you’ll start to lose detail.
We’re going to shoot for something less extreme, maybe around 5 or 10%. This keeps some of
the detail, but also gets rid of a lot of the noise. Sometimes, noise will look like small patches
of individual colors—the word for this is color noise. You can mitigate the effect by
increasing the Reduce Color Noise setting. Just be careful not to increase it too much,
or, depending on the image, the colors might start to bleed together. For most images,
we recommend a lower setting; I think 40% or 50% should do it for this one. Finally, reducing noise can also cause the
image to lose some sharpness. You can add the sharpness back using the Sharpen Details
setting. Just like Preserve Details, increasing this too much can cancel the effects of the
filter, so you generally want to aim lower. In this example, we’re going to set it to
about 10%, which should sharpen it just enough to make a difference. Keep in mind, you can use the same click & hold
method to compare the filtered version to the original. If you look closely, you’ll
see that the difference is pretty slight, but we did manage to reduce some of the noise. As you can see, there are lots of minor problems
that you may not have realized you can fix in Photoshop. Now you know how to sharpen
your images and reduce image noise, using two easy-to-use filters.