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Photoshop Tutorials For Beginners | Lesson 9: Sharpening Techniques
We always try to take pictures that are as sharp as possible 'in-camera'. But the vast majority of pictures can definitely be improved by some careful Photoshop sharpening techniques. So, in this tutorial I'm going to show you how to make successful, non-destructive sharpening edits. We'll discover how to sharpen an entire picture, as well as how to sharpen a small area within a picture. Let's get started...
Non destructive sharpening
Open a picture that you want to sharpen in Photoshop. As always, we're going to make this edit non-destructively. So, what's the first thing you should do? Yep, duplicate the background image, so that you have a new layer on which the sharpening will be made.
It's also important to say that sharpening tends to be the last step in the process of editing a photo. It's considered best practice to make changes to exposure, contrast, colour balance and so on, before finishing off with some sharpening.
Sharpening an entire image with the Unsharp Mask filter
Let's start with the simplest option: sharpening every part of a photo. To do this we will apply a filter. Make sure your Background Copy layer is selected and go to Filter>Sharpen>Unsharp Mask.
The Unsharp Mask dialogue box will appear, with 3 sliders that you can control:
|This specifies the intensity of the sharpening applied.|
|Radius:||This defines the area surrounding an edge that will be sharpened. A low setting means that only pixels really close to an edge will be sharpened. A higher number means that pixels further beyond the edge will be sharpened.|
|Threshold:||This determines what actually constitutes an edge. It's a measure of how different pixels must be from those surrounding them to be considered an 'edge'. Sharpening works on the edges within an image, so this is an important setting.|
Set these sliders to your desired amounts. I rarely move the Amount slider beyond 200, or the Radius beyond 2, or the Threshold beyond 3. Use the 100% preview window to guide you. Remember, it doesn't matter if you overdo it, because this is being applied to a layer. So we can always reduce the opacity later if needs be. Hit OK.
Having applied the Unsharp Mask filter, with your sharpened layer still selected, go to the blending modes drop down menu in the Layers panel and choose Luminosity.
This is a great tip. It applies the sharpening to the 'lightness' details, not the colour details, which dramatically reduces the sharpening side-affect of noise (graininess).
Rough'n'ready settings for different images
When sharpening with Unsharp Mask, you must use your own eye. You want the sharpening to look natural and not introduce noise into the image. But it would be helpful to have a rough guide to the settings that work for different images, wouldn't it?
Well, you're in luck! Below is a table that can be used as a rough guide. It's only a starting point though. I must say immediately that this is not my guide, but one created by Photoshop expert Scott Kelby. Mr Kelby is probably the world's most prominent Photoshop instructor, and I confess to being a fully paid up fan. He's a knowledgeable, infectiously enthusiastic and funny teacher.
|Portraits (much more intense sharpening is always applied to the eyes):||75%||2||3|
|Landscapes, property, product, still life:||225%||0.5||0|
|"Soft" things like flowers / people on the street:||150%||1||10|
|Architecture, coins, general hard edges:||65%||4||3|
|Pictures for the web (e.g. your Flickr streams):||400%||0.3||0|
|When you're just not sure, but you know some sharpening is needed:||85%||1||4|
Applying locally targeted sharpening (eyes in a portrait)
So, what about applying sharpening to a small part of an image, like the eyes in a portrait photo. Well, this is actually a more common thing to do than applying sharpening everywhere, which is a bit heavy-handed.
It is possible to use selection tools, like the Lassoo tool combined with Quick Mask, to select part of a photo and then apply an Unsharp Mask filter to it. But I much prefer to simply use layer masks (if you need to re-cap on masking basics, visit lesson 7: Using Photoshop Masks).
Open your image, a portrait photo is a good example. Duplicate the background layer and apply quite intense sharpening to the whole image. This is the level of sharpening that will ultimately only appear on the eyes. It will look too much for the whole face, but don't worry.
Now create a layer mask on your sharpened layer. Select the mask and press alt + backspace to fill the mask with black.
The sharpening will disappear. Remember, black hides and white reveals with masking. So select the brush tool, set opacity to 100% and choose white as the foreground colour. Zoom in really close on the eyes and carefully paint the sharpening back in.
We can be really precise with this method, and if we do slip over the edges, just switch the colour to black and paint over the mistake. Hit Cmd/Ctrl + 0 to zoom out and assess the results.
Applying sharpening to most of an image (e.g. landscapes)
Sometimes sharpening is the reverse of the above example. Instead of using a mask to paint sharpening in to a small area, we want to sharpen the whole image and remove it from a small area. This is often the case with sky in landscape photos:
Sharpening applies to edges, so smooth areas like an empty sky only show the negative side-affects of noise:
So the process is the same as above, except we do not fill the layer mask in black. Leave it white and set black as the foreground colour with the brush tool. Carefully paint over the sky to hide the sharpened layer, and eliminate noise.
Alternative methods: the sharpening tool and High Pass filter
The above methods are the ones I find most useful. But here are 2 other options you can experiment with. First, the Sharpen tool. This is represented by a triangle on the toolbar. It allows you to 'paint' sharpening directly on to an image.
So, duplicate the background layer and select the Sharpen tool. 100% opacity is much too strong for this tool, so reduce it to something in the region 20-40%. Paint over the area you wish to sharpen until it looks right. Clearly, this works best for very small areas, like eyes in a portrait photo.
Next, there's an alternative filter to Unsharp Mask called High Pass. Go to Filter>Other>High Pass.
As always, make sure you're working on a duplicated layer. Start by setting the Radius in the dialogue box to about 5 pixels. It will look peculiar: gray and slightly high-definition.
Hit OK and then change the blending mode of the layer to Overlay. This will return the image to normal, with increased sharpenss.
But the High Pass filter also influences tonal range and contrast, so it adds 'punch' to the image in several different ways. It's usually necessary to reduce opacity a little bit. I prefer the Unsharp Mask filter, but give this one a go and see what you think.
So that's the end of lesson 9! You're now equipped to sharpen your photos with a range of techniques in Photoshop. We've seen what the Unsharp Mask settings mean, how to use this filter for global adjustments, how to combine it with masking for local adjustments, how to use the sharpen tool and how to use the High Pass filter. I hope you found this tutorial helpful!
For a beginner-friendly book with step-by-step Photoshop tutorials, I recommend "Photo Nuts and Post" by Neil Creek.
Photoshop Tutorials For Beginners