Image after difusion and unsharp masking (selectively applying unsharp mask)
Difused Image
Original Image
I am sure you are well in touch with the option of unsharp mask.
Why use unsharpmask?
To restore the sharpness lost when turning the image into pixels, whether by scanning or direct digital capture.
How does unsharp maks work?
Sharpening works by increasing local contrast along edges. Typically, after sharpening some pixels that were almost white become pure white, and some pixels that were almost black become pure black. The black ones aren't too much of a problem, but the white ones can be.
Why this sharpening method is called unsharp mask?
The name has its origins in the conventional darkroom.In order to accentuate edges in a print and thus make it look sharper, the darkroom operator made something called an unsharp mask.
Why use unsharpmask?
To restore the sharpness lost when turning the image into pixels, whether by scanning or direct digital capture.
How does unsharp maks work?
Sharpening works by increasing local contrast along edges. Typically, after sharpening some pixels that were almost white become pure white, and some pixels that were almost black become pure black. The black ones aren't too much of a problem, but the white ones can be.
Why this sharpening method is called unsharp mask?
The name has its origins in the conventional darkroom.In order to accentuate edges in a print and thus make it look sharper, the darkroom operator made something called an unsharp mask.
The technique consists of creating a weak, slightly out of focus positive transparency of the original negative. Rather than exposing the negative on photographic paper, it is instead exposed on another sheet of film. Thus, this new version will be a positive image. Since we recorded it slightly out of focus, if we sandwich it with the original piece of film, all the edges in the composite image will have slight halos in the exact opposite color of whatever is on the other side of each edge.
These halos will be in the opposite tone of whatever is on the other side of each edge. When printed, halos will serve to darken along the edges making the edges appear slightly sharper due to the added contrasts.
There are three main controls in the unsharp dialoge box:
Amount controls how weak or strong the mask image that is blended in will be. Thus, it controls how much edge contrast will be added and how much apparent sharpness we will get. If set too low, we won't see any change at all, but if set too high, the inverted halos from the mask will be visible in the final image and it will look artificial
There are three main controls in the unsharp dialoge box:
Amount controls how weak or strong the mask image that is blended in will be. Thus, it controls how much edge contrast will be added and how much apparent sharpness we will get. If set too low, we won't see any change at all, but if set too high, the inverted halos from the mask will be visible in the final image and it will look artificial
Radius controls the degree of unsharpness the mask image will have. Thus, it determines the width of the halos the mask will produce. The higher the radius the more evident the sharpening effect will be. Set too low, the effect will be invisible or too subtle to be effective. The appearance of the halo will also vary with the content of the image since the amount of contrast already present will play a role.
Threshold selects how much adjacent pixels need to be to be considered an edge. Thus, it prevents sharpening of unimportant or incidental detail while reserving the effect for detail that should stand out. It separates signal from noise, if you will. Set too low, sharpening will be applied to every edge or change of tone throughout the image including such things as film grain. If set too high, no transitions will be viewed as being edges and no sharpening will result.
Note:
Sharpening (unsharp mask) shoud be done only at the end. This sharpening could be applied to selected areas. Sharpening is an art by itself, you have to decided what you have to sharpen and how much. Too much sharpening can result in noise.
Sharpening (unsharp mask) shoud be done only at the end. This sharpening could be applied to selected areas. Sharpening is an art by itself, you have to decided what you have to sharpen and how much. Too much sharpening can result in noise.
Selective application of unsharp mask
1. Select the original
2. Make a duplicate of it
3. Apply unsharp mask (you can exaggerate the application, no problem)
4. Add a layer mask ... Alt+click on add a layer mask option
5. Select a soft brush and set the opacity to 10 or which ever amount you like
6. Brush the picture whereever you need the sharpening.
7. Try out difusion or anyother options are per your need and creativity.
8. Looks good?
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