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high pass, how do you use it and what does it do. i can play with the slider but i dont know what i am accomplishing.
You can use it to sharpen photos and I've seen it used to bring out eyes. Here is the only tutorial I can find right now to use it. I'll try and find the others I've seen for you.
http://www.scrapbookmemoriestv.com/proj ... 1106_5.htm
HTH!!
The term 'high pass' stems from electronic devices used to filter high frequency signals to protect the signal from lower frequency signals.
http://en.wikipedia.org/wiki/High-pass_filter
I have mentionned it in my text about tools for sketching in one of the first newsletters.
What is a high frequency in a digital image? It is a sharp change in value between close pixels. Where there is a sharp edge, (ie change of luminosity) the frequency is high. If the transition is less sharp (blurred for example), the frequency is lower.
What you see with the filter with a low radius in Photoshop or Elements is a gray image with the edges enhanced, the lighter part of the edge is lighter, the dark one is darker. That is a kind of edge detector.
What use can this filter have? It can be used for edge detection and sketching, by using a threshold or gradient map in addition, for example. However, its most common use is to sharpen when used in a layer in overlay or softlight mode. Both blend modes increase the edge contrast by making the lighter side of the edge lighter and the darker one darker, hence a more visible edge.
What is interesting is what you see when using a large radius (30 to 50 for example). You get an increase which is much wider than the pixels near the edges or contours. This gives more depth, more three-dimensional look, just as USM with a large radius.

Edit:
Help for Elements:
http://help.adobe.com/en_US/PhotoshopEl ... 14D89.html
It is important to note that this is the exact opposite effect to gaussian blur.
Michel B
PSE6, 11,12,13.1 - LR 5.7 Windows 7 64 - OneOne Photo Perfect Suite - Canon 20D, Pana TZ6 - Fuji X100S
Most used add-ons: Elements+


Mes Galeries
I use high pass all the time for sharpening...make a duplicate layer run the high pass anywhere between 3 to 5 then set blend mode to softlight..lower opacity if to sharp. It is my favorite way of sharpening!!!
thank you both , i will note all this and experiment later.
Judy,

Some time back Dave Cross had a video tutorial on sharpening with this. The workflow is:

Duplicate background layer

Filter > Other > High Pass ... use the slider: the lower the number, the less you sharpen.

After you click OK, change the blend mode of that layer -- Hard Light usually works best

If too intense, lower the opacity of the layer or use the eraser to tone down specific parts of the sharpened image. If not sharp enough, delete the layer and reapply the filter with a higher setting.

I usually use USM but, via the slider, this lets you try to control which parts of the image are being sharpened.

Rusty
There is a very fine line between "hobby" and "mental illness" - Dave Barry

If your pictures aren't good enough, you're not close enough. - Robert Capa

www.prestophoto.com/photos/gallery/19932
thanks rusty, i appreciate it. I will absorb all the information later. They requested my presence at work today so i am gonna be a good girl and go.
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