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  #1  
Old 06-12-2005, 08:39 PM
HalloweenHJB HalloweenHJB is offline
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Default Unsharp Mask Settings

I apologize if this subject has already been discussed, but I would like advice on the "Unsharp Mask" settings in Photoshop. I have found settings that I like, but I wonder if anyone has any settings that work very well. Thanks in advance for your help!
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  #2  
Old 06-14-2005, 10:03 PM
jwmunro jwmunro is offline
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Default Re: Unsharp Mask Settings

Generally sharpening of an image is done case by case or on an image by image basis - in other words the image and its use dictates the settings. If the image has a lot of intricate detail you will need more sharpening than an image that does not. With that said start with the Amount between 120-200, the Radius between 1-2 but less than 2 and the Threshold at 0. Then based on the image add or subtract to the Amount until you get something good then adjust the others accordingly. Make sure the preview box is checked in the filter. Click the preview on and off to evaluate the results. Also, the amount of sharpening depends upon the output size and use of the image so sharpen after it has been resized for the intended use (last step in the process).

The above mentioned settings are my starting points and I usually go down from there.

Hope this helps.
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  #3  
Old 06-15-2005, 12:09 PM
greg greg is offline
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Default Re: Unsharp Mask Settings

I normally use radius .3 or .4, and amount 70-90% (threshold 0) for TE size screen images.
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  #4  
Old 06-15-2005, 09:01 PM
HalloweenHJB HalloweenHJB is offline
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Default Re: Unsharp Mask Settings --Thanks!

Many thanks for the response. I'll give it a try. HJB
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  #5  
Old 06-29-2005, 12:06 AM
AdrianW AdrianW is offline
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Default Re: Unsharp Mask Settings

There's also an interesting thread here, although I disagree with Philip's resize step. I agree with Ronners that converting to LABcolor and just sharpening the L channel is good. My workflow would be, resize to TE dimensions and then:

Step 1: Convert to LABcolor and select the L channel.

Step 2: First sharpening
(a) Go Filter>Sharpen>Unsharp Mask. Set Amount (A) and Radius (R) as follows:
- if the image has lots of detail and/or is not very sharp, A=20 and R=40;
- if it contains little detail and/or is already sharp, A=10 and R=20;
- if it's in the middle, set values in the middle. Click OK.

Step 3: Second sharpening
(a) Go Filter>Sharpen>Unsharp Mask. Set Amount=40, Radius between 1.0 and 1.5. Click OK.

Step 3: Third and final sharpening
(a) Filter>Sharpen>Unsharp Mask. Set Amount=20 to 30 (see what looks best), R=about 0.8. Click OK.
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  #6  
Old 06-30-2005, 01:45 AM
ronners ronners is offline
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Default Re: Unsharp Mask Settings

I read recently that another trick is to apply some gaussian blur (in PhotoShop) to the A and B channels in lab mode. This can have the effect of reducing noise in the image - which can be a side-effect of sharpening.
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  #7  
Old 06-30-2005, 05:51 PM
dimman dimman is offline
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Default Re: Unsharp Mask Settings

Try to put on the Adobe™ Photoshop the values of percentage 220 to 250 and a radius of 0.3 to 0.5 pixels with a level of no more than 4!!
This will be a satisfactory on a 3072x2048 pixel image, a typical 6,1 MP Tiff file, I insist on tiff file because it is a losels compressed file, and you’ll not face artifacts because of a typical JPG compression!
The key point is the radius that is measured in pixels! This means that the images pixel dimension is very important to examine before USM application!

Sometimes, if you have for example an image witch the detail counts a lot, like a stone wall, or grass, or a macro-shooting mosquito wing, the USM filter should be divided in, more than less equal values, and be applied 2 times!!

dimman
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  #8  
Old 06-30-2005, 06:04 PM
AdrianW AdrianW is offline
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Default Another option

Of course you don't have to use USM, there's another technique which can work well:
HighPass Sharpening

Often you'll find that a combination of USM and HighPass works best :)
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  #9  
Old 07-31-2005, 12:18 AM
AdrianW AdrianW is offline
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Default Re: Another option

As an additional step to the HighPass technique, I suggest you Desaturate after running HighPass - that should keep the colours more true to life :)
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