Manual Unsharp Masking p.133

[dpnew]

Hi,

I tried running through the steps for manual unsharp masking using the image lily.psd included on the cd, and it ruined the vibrancy of the color. So, I tried sharpening only the luminosity layer--same result. Finally, I tried using the Hidden Power tool on the luminosity layer, and I got the same result again.

I don't see how the manual unsharp mask does a better job than the unsharp mask filter: when I use the unsharp mask filter I get increased sharpness AND the same vibrant colors.

[Susan S.]

The manual "unsharp masking" is duplicating the photographic process- not replicating the unsharp mask filter of Elements. To quote Richard what this manual unsharp masking does is "to increase shadow detail and give a sharper look to the image" On the lily image that you used this on the shadow detail is already fine - reduction of contrast in the overall image is not what is required. This method would work well on overcontrasty images, where you also want to avoid the halo effect of light rings around dark objects. One that comes to mind (altho' i haven't tried it is) trees and twigs against a blue sky.

Susan S.

[dpnew]

Hi,

Thanks for the response.

I've got some high contrast images I'll try it out on.

[edit]
I tried manual sharpening on some high contrast images with branches outlined by the sky and the subject in the shadows, and it really brightened the shadows, and under extreme magnification, I can see that the halos are less with manual sharpening. However, my brief experiments reveal that manual sharpening is not for color images. It really muddies the colors. However, manually sharpening my high contrast image's Luminosity component did produce nice results, and in fact I thought the color in the shadows was even a little too saturated, so I used a Hue/Sat adjustment layer to tone it down, so I can see how manually sharpening has it's uses.
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[Richard_Lynch]

Actually, I can't remember how I set up the sharpening, but at the time I meant it as more of a demonstration. The implementation probably left out the intermediate step of splitting the Luminosity and Color. That is, the darkroom process had no real way of handling these separately (that i am aware of) and the approach in the book is to look at the idea of sharpening as it was in the darkroom and as a guide to the difference in how it is implemented (in really an opposite result) in Photoshop. As stated in the book, the two can be used together to enhance sharpening.

So, when you really want to apply this, it isn't the color you want to sharpen, it IS the Luminosity. When you split the two components, apply manual sharpening to the luminosity, and the color, being separate, will not be changed -- well, as a component. You will see that the appearance of the color can change as it is married to the tone -- tone changes (lightens/darkens), it has to affect the color result somehow. The key here is really seeing the two components individually (and the key, I think, to the book is seeing all the components as potentially separate, R, G, B, C, M, Y, K, Lum, color, spots). Like a building looked at from the outside, the image you see isn't just the color, the studs, nails, drywall, clapboard, paint all add up to the shapes you see...and each can be separated from the whole -- be that with difficulty, and in layers.

That help at all?

[dpnew]

Hi,

Thanks for the post. Yes, the information helps, and it confirms what I was seeing.

...the color, being separate, will not be changed -- well, as a component. You will see that the appearance of the color can change as it is married to the tone -- tone changes (lightens/darkens), it has to affect the color result somehow.

Yes, I understand the color does change because the tone changes when you manually sharpen the luminosity component of the image. Your book has taught me a lot about all the different components and how they affect each other. Thanks!

[dpnew]

For anyone else reading this thread, Richard Lynch addressed manual unsharp masking in newsletter #6:

http://www.hiddenelements.com/newsletter.html

The original process of sharpening that the Unsharp Mask filter is
named after uses a blurred, inverted duplicate of the original image
to pick out the edges. Try this:

1. Flatten a copy of your image and duplicate the background.
2. Invert the image (Cmd/CTRL+I).
3. Blur with Gaussian Blur 5-10 pixels.
4. Set the layer mode to Overlay, and reduce opacity to 50%.

This increases the contrast in the highlight and shadow for the image
(side effect being flattening the midtones). It can sharpen up detail
in high contrast images (wedding pictures) and is best used with a
midtone mask (rather than edge masking).