Photoshop seminar 3- selective sharpening

[Travis]

Note: My apologies to you dial-up users. This is an image-intensive lesson, and I had to use large files to illustrate the noise we're dealing with.

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If you have downloaded my actions, you know the great benefits of the "high-pass" filter. However, there can be a major drawback to sharpening. That drawback is added "noise." This can be a real problem if you're cropping or displaying larger pics. How bad depends on your sensor and varies with the color and sharpness of the area of the photo. If you've ever seen a pic with a "grainy" look, that's noise.

The noise will be worst in areas that are out of focus. The areas in focus generally handle sharpening the best, while parts not in focus (especially the background) will show tons of noise when sharpened.

In this little class, I'll teach you how to "paint" the sharpening (or any other effect) on to only the part of the photo where you want it, namely your subject (if that's not in focus, you need to get rid of the pic- sharpening won't help you there).

Now, there are two ways to do this that I know of. I'll go over the first and easiest method here.

OK, here's our sample pic before sharpening:







Here's a cut of the background at 100%:







Here's the sample pic after sharpening:







And a cut of the background, post-sharpening, at 100%:







At this point, you will have run your high-pass filter and if you blow up the background to 100% should notice the added noise. If not, go to your "Layers" palette and click the eyeball next to the top layer on and off- this shows/hides the high-pass filter. As you clik on and off, you will be able to see the difference. Now, here's how to fix it.

Go to layer--> add layer mask-->hide all







The sharpening effect wil disappear. Don't worry, it's not gone. You're just going to "paint it on" to only the places where you want it. In your main toolbar, make sure your fore/background colors are black and white by clicking on this:







Now, click on the brush tool on the same toolbar. Then, carefully drag the brush around the edges of your subject. You want to get all the edges, but you want to avoid painting over background where possible. Don;t try to be too perfect your first few tries, just try to keep it inside the fish. Now, to see your progress, in the layers palette click the eyeball icon next to your "background layer" so the eyeball is off. You now see what you have painted on in the high-pass layer. It should look like this:







Now, paint the inside of the fish using the boundaries you have created. When done, click the background layer back on. Voila! Your fish (or other subject) is sharpened, but nothing else is. (Since the algae in this shot was in focus, I sharpened it as well.)

Here's your finished product:







And here's that 100% blowup showing no additional noise in the background, but you can see where the fish has been sharpened:







Now, just flatten your image and you're done!

[Travis]

-side note- if anyone has ever heard of "chromatic aberration" and wonders what it is/looks like, check out the bluish-purple fringing on the 100% blow-ups. That's chromatic aberration.

T

[Boomer]

Now Trav that was cool. Despite all the time I spend in PS I don't really get into all that fancy stuff

[Cougra]

Thanks again Travis! That's going to take a bit of practice to get this part done right! I'm horrible at outlining things in photoshop

[EdgeKrusher]

Just a couple of questions.

At this point, you will have run your high-pass filter and if you blow up the background to 100% should notice the added noise. If not, go to your "Layers" palette and click the eyeball next to the top layer on and off- this shows/hides the high-pass filter. As you clik on and off, you will be able to see the difference. Now, here's how to fix it.

Go to layer--> add layer mask-->hide all

Do we apply this option when the High pass filter is visible?

Now, click on the brush tool on the same toolbar. Then, carefully drag the brush around the edges of your subject. You want to get all the edges, but you want to avoid painting over background where possible. Don;t try to be too perfect your first few tries, just try to keep it inside the fish. Now, to see your progress, in the layers palette click the eyeball icon next to your "background layer" so the eyeball is off. You now see what you have painted on in the high-pass layer. It should look like this:

Once we select the brush, then what? IS there a special brush that will paint the outline of the fish?

After running the high pass filter I get lost. I'm not sure on how you are "painting" the fish onto anything. I've read this 6 times and I just don't understand how you get the final product. I see it, but your instruction seems to be missing something.
we all appreciate these Travis.
Thanks

EK

[Travis]

Hey EK, I'll admit these things are very difficult to describe.

This may help…

Think of your high-pass as a filter. Using this technique, when you use the brush tool to paint, instead of painting a color, the “ink” coming off the brush is the actual filter. So you just paint over the places where you want the filter to go, instead of applying it to the whole image.

Here’s the simplified approach. If you follow these steps, it should work.
1. Run high-pass.
2. Layer‡add layer mask‡hide all
3. click on brush tool
4. cover your entire subject using the brush tool.

AFAIK, The only situations where following the exact steps above would not work:
1) your high-pass isn’t on a new layer (there should be two after running the high-pass)- Download the reef-life Actions v.2 and the action should automatically do this for you.
2) You didn’t click the button on the tool palette that sets your foreground color to white and your background color to black. See the image with the arrow painted on above.

[Travis]

Sorry, in answer to your questions-

1- yes, the high pass layer should be visible and active (highlighted) on your layers palette when you do this.

2- no special brush required, but it should be one with a soft edge. I use the "[" and "]" keys to make the brush bigger or smaller as needed. Smaller around the edges for precision, bigger when filling in the inside to save time.

[EdgeKrusher]

Thanks Travis!

After reading those last two posts it makes perfect sense.

EK