How to Sharpen Images


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cichlid

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Dec 2, 2006
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Hi all

How do you all sharpen your images in Elements or CS?

Do you use Unsharp mask or adjust sharpness?

If using unsharp mask, how to set the Amount % , Radius pixels and threshold?
 

cs 2

unsharp mask, try to limit your radius pixels.. how much depends on the size, amount should not go beyond 100% as far as i can see

best is to zoom in 100% so you can see what you are doing to "degrade" the image

if you are posting websize can go a little more aggressive, when resize cannot see the jagged little edges/haloing hurhur

here is another way, works for certain pictures very well :)

if you wonder what all the parameters mean, i quote:

Radius controls how wide the edge rims become, and Radius = 1.0 is about the right ballpark, with 0.6 to 2.0 often being useful. Higher Radius values can cause halos at the edges, a detectable faint light rim around objects. Radius units are not the same as pixels, the units step in tenths, but the Radius width is usually at least 4 pixels overall, you will see various effects. Radius is a very important parameter, and the easiest way to ruin a good scan is with too much Radius. Inanimate objects can use the most radius, human faces can tolerate the least, and landscapes fall in between. But it really depends on the size of the details. Fine detail needs a smaller Radius, or else you may obliterate tiny detail of the same size as the Radius width. Large images have larger detail (more pixels involved) and can use more Radius, so therefore printing at higher resolution can support the larger radius. Radius and Amount interact, reducing one allows more of the other.

Threshold specifies how far apart adjacent tonal values have to be (values of 0..255) before the filter does anything to the edges, before it is judged to be an edge at all. This lack of action is important to prevent smooth areas from becoming speckled. Low values should sharpen more because fewer areas are excluded. Higher threshold values exclude areas of lower contrast. Human faces want values greater than 1 or 2, like perhaps 5 or more. For inanimate objects, perhaps 0 or 1 is useful. General work, try 3 or 4. This control has little effect at high values, but has more effect changing between low values of 0 to 5. This Threshold is not to be confused with Line art Threshold.

Amount is like a volume control, exaggerating the edge differences (how much darker and how much lighter the edge borders become). Amount interacts with Radius as to degree of sharpening, but it does not affect the width of the edge rims. Amount has a large effect, and values of 80 to 120 are normally usable if the Radius isn't too large.
 

Use unsharp mask, depending on whether is it for web or print. Range from 85-100%. Radius usually use 1. For threshold depending on the intensity, 1 for major sharpening and 5 for subtle changes
 

ok thanks guys

no wonder my pics look horrible,

i think the Amount is more than 250% .
Radius 65.7 pixels and
Threshold 135 levels

:bsmilie:
 

Mmm... I find the following works well to start with, then adjust to suit the picture:

For picture size of about 900 x 600px:
Amount: 50 - 70%
Radius: 0.5
Threshold: 3

For picture size of about 500 x 333px:
Amount: 30 - 50%
Radius: 0.5
Threshold: 3
 

For me...

Amount: 30 - 200% (depending on image size and how aggressive I need it to be sharpened)
Radius: 2
Threshold: 10
 

will this method reduce handshake blur? thks
 

Depends on how much blur you're talking about. Get it right when you shoot. The original intention of sharpening is not for correcting a mistake, but rather overcoming lens/sensor limitations for sharpness.
 

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