Kens Photoshop Blog

Some people just want to click a few buttons and pull up a filter without being bothered with knowing what to do, when and why, and that’s fine I guess, but a skilled photoshop user that knows how sharpening works and how to apply it intelligently will beat any plugin any day, if the preset point and click way is your preferred way of working you can safely hit your browser back button now

Sharpening at its core, is simply enhancing edge contrast, once you understand this, you will soon see why all the filters in the world will come up short against a set of human eyes, and are simply replaying a set of actions to do the work for you, but they can’t see the image like a human and they can’t make intelligent choices based on what is actually IN the image, they can make your wallet lighter though

In the following tutorial I will show some of the common sharpening techniques and how to apply these non-destructively to your photos.

UPDATE
If you are using a version of Photoshop that has smart object, by all means start using them. In the instructions below, whenever I say set the layer opacity to 50% and apply a filter, instead convert the layer to a smart object and then apply the filter, that way even the copies of the layers are non-destructive and you don’t need to adjust the strength with layer opacity since you can just dubleclick on the smart filter and re-adjust as much as you’d like.

The ultimate sharpening approach must give us 4 things:

• It must be non-destructive.
• It must allow us to adjust the amount at any time.
• It must allow us to adjust opacity of both low and high contrast areas.
• It must allow us to selectively apply it or remove it from any part of the image.

Open any image that you’d like to work with, now select the background layer from the layers palette and hit Control+J to make a copy of it.

Select the new layer, set the opacity to 50% (You can hit the 5 key on your numeric keyboard to do this while in the layers palette) now go to filters and select unsharp mask, and apply a quite strong amount of sharpening to it, never mind any color aberrations and halos, we will take care of this later, hit OK to apply the sharpening.

Make a copy of the layer you just sharpened so that you now have 2 identical and sharpened layers.

Select the first copy and name it “Shadows” and set the blending mode to “Darken”

Select the second copy and name it “Highlights” and set the blending mode to “Lighten”

Let’s clean everything up a bit, select the 2 new sharpening layers (hold control and click each one) and then hit control+g, now you have grouped these 2 layers into a group, doubleclick the group label and name the group “Sharpening”

Now select the group itself, the blending mode for the group should now say “Passthrough”, change it to “Luminosity”

Let’s add the masks now, select the “Shadows” layer and go to the “Layer” menu and select “Layer mask” and then “Reveal All”, do the same for the “Highlights” layer, you won’t see anything change yet.

Finally select the group itself (Sharpening) and add a “reveal all” layer mask to the group as well.

Phew, if you made it this far, good job, we are now ready to take a look at what we have accomplished in the next section…

So what have we accomplished here?

We have a non-destructive sharpening group, the group contains a separate layer for the sharpened highlights and one for the shadows, this is so we can fine-tune how much sharpening we want to apply to the shadows and highlights individually, frequently the highlights needs less sharpening to avoid haloing around the edges in the image, since both the layers are set to 50% opacity we can tweak the opacity up or down to get them just right.

We have put both of the layers into a group so we can turn the whole shebang on and off to compare the results easily, and we have set the groups blending mode to Luminosity, Luminosity mode only lets the, well uhm luminosity pass though, meaning we can’t get any chromatic abberarions such as colored haloing.

Finally we have put separate masks in both the shadows and highlights layer AND the whole group as well, why did we do that?

Well the magic here starts once you have fine-tuned your overall sharpening, we can now select any layers MASK (Important, select the mask NOT the layer) and hit control+I (Invert), this turns the white mask black, and a black mask hides everything, after you invert the mask (Start with the group mask, it’s easier to see the results) select your brush tool (Hit B) and then paint with WHITE over the areas you want to “paint with sharpness”, see how you can now sharpen selected areas only so you can easily paint over the subjects you want to sharpen and not have background blur and noisy areas sharpened which would increase the noise, paint with a brush set to low opacity so you can slowly brush over it and paint more and more sharpness in, for example if you have a photo shot with low aperture and a shallow depth of field you’d want to paint in more sharpness around the area in focus and slowly fade the sharpness out as the background blur increases.

This level of control is simply NOT possible with a plugin no matter how good it is, it can’t see the image but YOU can.

Something for the really hardcore control freaks.

What if I want have control over my midtones, what THEN Mr.Sharpening wizard, WHAT THEN HUH?

OK ok, let go of my arm crazy person, jeeez…

Go to your sharpening group, create a duplicate of any of the layers, doesn’t matter, and set the blending mode to normal, since the group blending mode is set to Luminosity we are safe from color halos, since this effect is going to be REALLY subtle turn of the Shadows and Highlight layers for now.

Name this new layer “Midtones” and doubleclick to open the layer styles dialog. Don’t click anything, see down there where it says “Blend If” ?

Don’t mess with the dropdown, it should say “Gray”, now you can adjust the “This layer” black and white sliders and set them towards the middle, this selects the midtones in the image, this creates a very hard transition, but you can split the black and white sliders in half, click on either left of the right side of the little slider arrows while holding down the ALT key and drag, this will split the slider into 2, this applies a feather to the range you have selected, the further apart the more feathered the range becomes.

Luminosity and Density masks more ways to control your sharpening.

Instead of using the Darken and Lighten blending modes, you can create special masks derived from your image to control sharpening of the shadows and highlights

Luminosity is the light levels in your image, To get a Luminosity mask, first select the background layer from the layers palette and make a copy of it by hitting control+j, set the layer opacity to 50% and then go to your channels palette, now look at the channels and find one with good contrast between the light and dark areas of the image, now hold down control and click on the channel thumbnail, this will load the image Luminosity as a selection. Go back to your background copy in the layers palette and click the layer mask thumbnail, you now have a Luminosity mask on your image, the 50% brightest values are selected via the mask, you can now go ahead and chose Unsharp mask and apply sharpening to the brightest parts of your image.

To get a Density mask, which is the 50% darkest parts of the image, simply copy the Luminosity layer with the mask, then select the mask and hit Control+I to invert it and you now have a Density mask, with only the 50% darkest parts sharpened.

Since you set the opacity to 50% you can now adjust the opasity up or down to your liking.

Edge masks, special attention to strong edges.

If you look at a photo, you should see areas of larger edges that has more contrast between them, outlines around objects for example, sharpening these can really make your photo pop, but it’s impossible to paint these with sharpness, well not impossible, but way to time consuming, this is where Edge masks comes in handy.

Most people have probably played around with all the filters in photoshop, who have not gotten to the ‘Find Edges’ filter and thought “whoa cool, but who the hell would use this?”

Well as most people find out as they progress and get more skilled in Photoshop, almost everything has a specific use, even though it’s not always obvious, so let’s see what the real purpose of the Find Edges filter is.. Edge Masks

First we need to check out the channels info in the image, what we are looking for here, is the channel with the most contrast between edges, strong black and white edges. Once you have made your choice, grab that channel and make a copy of it and name it edge mask. Now comes the magic, go to your filters menu and select “find edges”

By now, we have a decent, but not great edge mask, we need to enhance it, so bring up the levels dialog (Control+L) and adjust the white and black sliders towards the middle, you just want to make the black areas totally black, and the white areas totally white, hit OK when done.

Now we have a very sharp edge mask, to sharp in fact, we want a bit of feathering so we go to the filters menu and select “gausian blur”, add a tiny amount of blur, just enough to make the edges visibly blurred, but not so much as the smallest edges start to blur into each other.

Now we bring up the levels again, since you blurred the edges, you can now use the black slider to grow the size of the edges and the white slider to choke them, grow the edges so they are as large as you can make them without any edges blurring into each other.

Ok, almost done, if you look at the edge mask now, you will notice that the edges are black and the rest is white, since black hides and white reveals when using masks, we want to invert the edge mask now, so select it and hit Control+I

All done with the edge mask, now to put it into play, go to your layers palette and grab a copy of the background layer. now go back to the channels palette and click on the edge mask while holding down control to load it as a selection, then go back to your background copy and click the “add layer mask” button in the layers palette.

Now select the layer itself, go to Unsharp Mask or Smart Sharpen, whichever you are more comfortable with and apply a strong amount of sharpening, toggle the preview on and off and look at the full image as you do, notice how ONLY the edges are getting sharper, the large areas around the edges are untouched and not sharpened.

If you find the edges are to large, or not large enough after you sharpen, you can select the layer mask and do a levels adjustment (Control+L), remember that pulling the black slider expands the mask, and pulling the white slider chokes the mask, you can even blur the mask a bit more and then do a levels adjustment if you need to choke or expand the mask even more.

Couple the edge mask with the total control mask and you have miticoulous control over sharpening any part of your image down to the most ridiculous detail.

HIRALOAM Sharpening.

HIRALOAM or High Radious, Low Amount is a special form of sharpening that is designed to enhance shape, not fine detail.

The recipe is simple, in the unsharp mask dialog, set amount to 500, we are not going to actually use such a redicoulously high setting, we are just using it to easily see what we are enhancing.

Now adjust the radious so you can see the halos caused by the high amount setting, the halos should surround the basic shapes of larger objects in the photo, so adjust until it matches, then turn the amount back down to something low like 40-50 and you are done.

Now try and flip preview on and of to realy see what it has done, notice how the small details are not affected, but it has enhanced the shapes of objects