Super sharpening technique for CS2

fmw

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The latest issue of Photoshop User magazine has a really effective technique for applying sharpening to an image without all the bad side effects of oversharpening. It uses the unsharp mask on the inverted lightness channel in the lab color mode. This channel has all the detail information. The article shows you how to set the process up as an action so you can repeat it easily each time you want to use it. Here goes.

1. Load an image that needs sharpening. Make it a high res image so the numbers that are included later don't over do things. Then start the recording process in the actions palette. Window>actions. Click on the "create new action" icon, name the action and click "record"

2. Switch to Lab Color mode. image>mode>lab color
3. Open the Channels palette - windows>channel, select the lightness channel - Control-Alt I.
4. Invert the selection - Control-Shift-I
5. Activate the lightness channel by clicking on it in the Channels palette. The image will probably turn monochrome because the lightness channel has no color information. click on the eye icon and move on. Use unsharp mask - filter>sharpen>unsharp mask. Put 500% in the amount box, 1 in the radius box and 2 in the threshold box. Click OK.
6. Make a second pass. This time make the amount 50%, radius 20 and click OK.
7. Deselect the lightness channel - select>deselect.
8. Return to RGB mode - image>mode>rgb color. Now you can go to the actions palette and click the stop recording icon.

That's it. Any time you want to repeat this process on another image just go the actions palette, select the action as you named it and click the play button.

If you are working on a lower res image use less extreme settings in unsharp mask.

This method works very well. Highly recommended.
 
wow that really does do a great job! thank you!
 
You're welcome. I now use this method all the time for high res or large output. It's the best method I've seen.
 
google the "hi pass" filter, there's an excellent tutorial online and this is what I do for "super sharpening" shots.
 
I also use the highpass method of sharpening...but I'm always willing to learn new things.

I tried this method...but as I'm only on CS...somthing doesn't work.
Open the Channels palette - windows>channel, select the lightness channel - Control-Alt I.
Control-alt I, opens up the image info. What exactly are you selecting when you do this?
 
Big Mike said:
I also use the highpass method of sharpening...but I'm always willing to learn new things.

I tried this method...but as I'm only on CS...somthing doesn't work.

Control-alt I, opens up the image info. What exactly are you selecting when you do this?

Control Alt I inverts the selection
 
fmw said:
Control Alt I inverts the selection
Control SHIFT I, inverts the selection.
Control Alt I, opens up the file info box.

What I need to figure out is this...when you open the channels pallet...then what? You said to 'select the lightness channel'. Does that mean to click on it in the pallet? Like making a layer active? Or do you make an actual selection of something?

I can't invert the selection, if I don't have anything selected...so what do I select?

:confused:
 
Big Mike said:
Control SHIFT I, inverts the selection.
Control Alt I, opens up the file info box.

What I need to figure out is this...when you open the channels pallet...then what? You said to 'select the lightness channel'. Does that mean to click on it in the pallet? Like making a layer active? Or do you make an actual selection of something?

I can't invert the selection, if I don't have anything selected...so what do I select?

:confused:

Yes you click on it in the pallet to make it active. When you do that, the image will become monochrome (if it was color) so you'll know you selected it. Then you can invert.
 
I think I figured it out...but I'm still having trouble with your instructions. (I'm not trying to be a jerk...just trying to make sure I'm doing it right)

I change to Lab mode...then to select the lightness channel I hit Ctrl-Alt-1. I don't 'invert' (as in image/adjustments/invert)...but I inverse the selection Shift-Ctrl-I. Then I click on the lightness channel in the pallet, (it turns monochrome), then run the two sharpening passes, deselect and return to RGB mode.

It looks pretty good...so I think I've got it right....but in the process of figuring it out, I ended up with a bunch of inverted images...purple sky etc. :lol:
 
fmw said:
The latest issue of Photoshop User magazine has a really effective technique for applying sharpening to an image without all the bad side effects of oversharpening. It uses the unsharp mask on the inverted lightness channel in the lab color mode. This channel has all the detail information. The article shows you how to set the process up as an action so you can repeat it easily each time you want to use it. Here goes.

1. Load an image that needs sharpening. Make it a high res image so the numbers that are included later don't over do things. Then start the recording process in the actions palette. Window>actions. Click on the "create new action" icon, name the action and click "record"

2. Switch to Lab Color mode. image>mode>lab color
3. Open the Channels palette - windows>channel, select the lightness channel - Control-Alt I.
4. Invert the selection - Control-Shift-I
5. Activate the lightness channel by clicking on it in the Channels palette. The image will probably turn monochrome because the lightness channel has no color information. click on the eye icon and move on. Use unsharp mask - filter>sharpen>unsharp mask. Put 500% in the amount box, 1 in the radius box and 2 in the threshold box. Click OK.
6. Make a second pass. This time make the amount 50%, radius 20 and click OK.
7. Deselect the lightness channel - select>deselect.
8. Return to RGB mode - image>mode>rgb color. Now you can go to the actions palette and click the stop recording icon.

That's it. Any time you want to repeat this process on another image just go the actions palette, select the action as you named it and click the play button.

If you are working on a lower res image use less extreme settings in unsharp mask.

This method works very well. Highly recommended.

Great method, but like Mike, i struggled with the instructions

for step 3 it's easier to simply click the lightness channel. The keystrokes in the method open a window for adjusting image size

step 4 - inverting the selection is impossible since nothing has been selected. I presume you meant Control_I to get the inverse of the image.

sharpening in 2 passes is no problem.

and a missing step is to re-inverse your layer by pressing control-I again. if this is missed then the image looks way too weird.

and conversion back to RGB is fine.

Of course it maybe depends on what version of PS you have. I have PS CS2 so i had to follow a slightly different procedure from the instruction.

But the method does work a treat and i now have a nice action for my images. Nice one :thumbup:
 
There is a mistake in the method. You do not press ctrl+alt+I, you hold control and click the lightness channel. This loads it as a selection. Then you invert that selection (shift+ctrl+I), and do your sharpening.
 
Sorry about the instructions. The method, however, is very effective if you can wade through the process. The advantage of making it an action is that you don't have to go through the process every time.

The whole purpose of the thing is to do the sharpening only in the L channel where it makes a difference and it avoids any side effects by having the sharpening take place anywhere else. At any rate, if works great.
 
I'm on PhotoShop 7, but I can still doing everything as explained in the results so I don't think that should matter...

I think I'm following the instructions correctly but the only results I get are horrendously over-sharpened. This is what I'm doing:
1) Convert to Lab
2) Go to Channels and click the Lightness channel so it is the only one that shows up as selected (blue)
3) Cmd+Click (on a Mac) on the Lightness channel
4) Select>Inverse
5) Sharpen at 500%, Radius 1, Threshold 2
6) Sharpen at 50%, Radius 20, Threshold 2

Throughout this, the only channel selected is Lightness. Someone please shed some light on my error!
 

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