unsharp mask in photoshop - how?

Application or situation Amount Radius Threshold
All purpose 85% 1 4
For the Web 400% 0.3 0
Soft subjects (people, pets, etc.) 150% 1 10
Portraits 75% 2 3
Moderate sharpening 225% 0.5 0
Maximum sharpening 65% 4 3
 >> Stay informed about: unsharp mask in photoshop - how? 

THO wrote:
> I'm rather baffled by photo sharpening in Photoshop. I've seen the
> results of sharpening in Picassa but I can't figure out what the best
> numbers are to enter into Photoshop. Does anyone have any guidelines
> that they can share?

I attended a workshop a while back where I learned a rule-of-thumb
that greatly simplifies Unsharp Mask:

* If Amount is less than 400%, keep Radius fixed at 0.4 px.
* If Radius is greater than 0.4, keep Amount fixed at 400%.

This removes one variable, so you basically have only one control to adjust.
Start with, say, Amount=50, Radius=0.4, adjust Amount upwards until it
looks good, and if you reach 400, keep it there and start increasing Radius
instead.

This is all done with Threshold=0. You can try increasing the Threshold
afterwards to remove noise in the low-detail areas, or (as we did in the
workshop) you can use some sort of edge mask to inhibit sharpening
in low-detail areas.

The actual numbers you need will depend on the image dimensions, how
much in-camera sharpening has already been done, how much resizing
you've done, how sharp the focus is, etc, etc. For web-sized images
from my DSLR, I usually need Amount in the 50-150 range and Radius 0.4 .
For print-resolution images I might go as high as 350/0.4.

Depending on the image, you might also want to do a second, high-radius
sharpening pass to increase the local contrast. For this, keep Radius
at 50 px, and try Amount in the 5-15 range. This can work wonders for
images that need a contrast boost.

-Joe
 >> Stay informed about: unsharp mask in photoshop - how? 

In article <tho-5C0396.17411426042007 RemoveThis @news.giganews.com>,
THO <tho RemoveThis @tho.tho.23.invalid> wrote:

> I'm rather baffled by photo sharpening in Photoshop. I've seen the
> results of sharpening in Picassa but I can't figure out what the best
> numbers are to enter into Photoshop. Does anyone have any guidelines
> that they can share?
>
> Many thanks.

If you have CS 2, try using smart sharpen. If you have any further PS
questions, consider posting them on comp.gaphics.apps.photoshop
 >> Stay informed about: unsharp mask in photoshop - how? 

In article <tho-5C0396.17411426042007.RemoveThis@news.giganews.com>,
THO <tho.RemoveThis@tho.tho.23.invalid> wrote:

> I'm rather baffled by photo sharpening in Photoshop. I've seen the
> results of sharpening in Picassa but I can't figure out what the best
> numbers are to enter into Photoshop. Does anyone have any guidelines
> that they can share?
>
> Many thanks.

Unsharp mask lets you tune the sharpening diameter. Small diameters
help bring out fine details while larger diameters can help boost the
contrast in a dull image. Sometimes multiple passes are needed, like a
small diameter to fix minor focus blur plus a very large diameter to
clean up haze.

I usually slide the level control back and forth to preview how well the
diameter matches what I'm trying to correct. Look for how it causes
ripples or halos. When the diameter matches, I turn down the level
until the picture looks clean and natural.
 >> Stay informed about: unsharp mask in photoshop - how? 

"THO" <tho.DeleteThis@tho.tho.23.invalid> wrote in message
news:tho-5C0396.17411426042007@news.giganews.com...
> I'm rather baffled by photo sharpening in Photoshop. I've seen the
> results of sharpening in Picassa but I can't figure out what the best
> numbers are to enter into Photoshop. Does anyone have any guidelines
> that they can share?
>
> Many thanks.

I have two quite different sets of parameters from which I start in
Photoshop.
(Most of my images are jpegs from a Canon 5D [default settings], using prime
lenses at around their optimum apertures. I also use RAW and find different
settings can give better results.)

For sharpening - last process, just prior to printing,
Amount 200%; Radius 0.6 pixel; threshold 4 levels
Images are normally viewed at 100% to check on the effect. Haloes?

For general lift of contrast to combat aerial mistiness and similar (Kit
zoom lenses seem to need this quite often.)
Amount 30%, Radius 60 pixel, threshold 0 levels. Normally applied early on.

HTH

--
M Stewart
Milton Keynes, UK



--
Posted via a free Usenet account from http://www.teranews.com
 >> Stay informed about: unsharp mask in photoshop - how? 

Malcolm Stewart <malcolm_stewart.TakeThisOut@megalith.freeserve.co.uk> wrote:

> "THO" <tho.TakeThisOut@tho.tho.23.invalid> wrote in message
> news:tho-5C0396.17411426042007@news.giganews.com...
> > I'm rather baffled by photo sharpening in Photoshop. I've seen the
> > results of sharpening in Picassa but I can't figure out what the best
> > numbers are to enter into Photoshop. Does anyone have any guidelines
> > that they can share?

Small radius settings emphasize detail, large radius settings emphasize
shape.

The threshhold setting helps you avoid sharpening noise or graininess.
Of course, whenever I've used it that way I end up with some noise
that's not sharpened with a halo of noise around it that is. O well.

[..]
> For general lift of contrast to combat aerial mistiness and similar (Kit
> zoom lenses seem to need this quite often.)
> Amount 30%, Radius 60 pixel, threshold 0 levels. Normally applied early on.

The best thing in the world for misty or hazy scenes is to switch to LAB
mode and tweak the contrast on the L channel with a curve.

Also, sharpening the L channel alone keeps the colors more natural while
emphasizing the details. The effect is much more subtle, and can happen
early in the process.

--
http://www.xoverboard.com/cartoons/2007/070416_argument.html
 >> Stay informed about: unsharp mask in photoshop - how? 

And lo, THO <tho.RemoveThis@tho.tho.23.invalid> emerged from the ether
and spake thus:
> I'm rather baffled by photo sharpening in Photoshop. I've seen the
> results of sharpening in Picassa but I can't figure out what the best
> numbers are to enter into Photoshop. Does anyone have any guidelines
> that they can share?
>
> Many thanks.

As with most things in digital imaging, sharpening is more art than
science. Personal preferences and different circumstances may call for
varying approaches and magnitudes.

First of all, be sure that you aren't judging the overall sharpening
effect of Unsharp Mask on your image based on a zoomed-out view. In
other words, use the little preview window within the filter dialog
itself, and/or zoom the image to 100% to make sure you perceive the
sharpening at its true size. Many people unfortunately oversharpen
their images because they view the effect while zoomed out.

Sidebar: in Photoshop, you can zoom the image in and out while the
filter dialog is open by using Ctrl-plus and Ctrl-minus (or on the
Mac, Command-plus and Command-minus). You can also pan the zoomed
image around by holding the spacebar in the same way you would outside
of the filter dialog.

Second, there are quite a few third-party packages that can aid your
sharpening adventures. Nowadays, "intent sharpening" is coming into
vogue. With intent sharpening, your initial photo is sharpened lightly
at first to reverse the effect of the anti-moire filter in your
camera. Then, artistic (or "creative") sharpening may be used to
increase the clarity of certain elements within the image. Finally,
the image is resized (if necessary) and sharpened a third time
depending on how it will finally be used, either for the web or for
print, etc.

It turns out that sharpening for print typically makes the image look
absolutely terrible on-screen, but can significantly improve the
quality of the print.

PhotoKit sharpener is a nice tool basically consisting of a bundle of
Photoshop actions packaged as an automation plug-in. It was written by
some of the core Photoshop guys and photographic pros; Bruce Fraser,
Jeff Schewe, Martin Evening.

There are plenty of other tools, and they are all worth examining.

--
Aaron
http://www.fisheyegallery.com
http://www.singleservingphoto.com
 >> Stay informed about: unsharp mask in photoshop - how?