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04/29/2005 07:41:35 PM · #1 |
Are they over sharpened
 
 
They all were taken at the Louisiana International Music Festival in Lafayette. |
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04/29/2005 07:47:35 PM · #2 |
| I don't know myself much about using USM, but I believe that these would be considered over-sharpened due to the "halos". |
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04/29/2005 07:50:26 PM · #3 |
I would say us for 1-3...4 is harder to tell because of the pale background. I like the Red Hats. :)
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04/29/2005 07:51:41 PM · #4 |
| probably, but i don't mind a little oversharpening myself. red-hats is a really great shot. |
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04/29/2005 08:15:47 PM · #5 |
Yes, If you can see white halos, "Mackie Lines", (which are lines along edges where light and dark areas meet) you have over sharpening.
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04/29/2005 10:45:20 PM · #6 |
I went to a store today where a member from canon was talking about sharpening. He suggest this as a starting point with USM:
sharpen: 100%
Radius: 1.0
Threshhold: 2
Signs of oversharpening: increased grain in large areas of one color like blue skys, and glowing edges like the ones in your first photo(try sharpen edges to avoid glowing edges)
I am no expert this is just what I learned today and I have yet to use this strategy. Hope this helped |
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04/29/2005 10:53:55 PM · #7 |
| Yeah, a little overly-sharp, but nice nonetheless. It almost looks like a celebrity lineup - Hilary Clinton in a red hat, Mike Ditka playing the "fiddle," Chuck Magione (sp?)on bass (or whatever that is)and one anonymous guy on the tuba? |
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04/29/2005 11:24:25 PM · #8 |
Unsharp Mask sharpens images by increasing the contrast between adjacent areas. It does this by creating two borders around the contours, a darker and a lighter border (increased or decreased according to the radius setting). If you look at the Halo-Mackie-Lines.jpg posted by mpemberton, you can see both the darker and lighter borders. The intensity of these borders created by USM is controlled by the amount slider of the settings.
A trick for reducing the light halo so that it is not as noticeable, or even completely eliminated, is to use fade unsharp mask (found under the edit menu). After applying the unsharp mask bring up the fade unsharp mask box and set the mode to: lighten (this will work on the lighter halo. Then you can reduce the opacity slider until the light halo is reduced to where it's not noticeable, or you can completely eliminate it by setting it to 0%. This will just leave the darker halo, which is much less noticeable. |
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04/29/2005 11:26:57 PM · #9 |
Ok I really want to get this shapening stuff right. I can see the halos on the pic mpemberton posted and of course he has done it to the extreme for example. But looking at my Mike Ditka fiddler and the red hat pics, for whatever reason I do not notice halos.
If anyone has the time to be very specific as to where there is over sharpening I may someday be able to repay in kind.
Well, I went back and examined the photos before posting this and after looking I can see some halo effect on the hat on the lady at the right hand side. I think I am also noticing it along the fiddler̢۪s right shoulder and back. I don̢۪t really notice on the other two images.
I have also heard a little over sharpening for printing is a good thing, yes or no?
I know I am asking a lot but I need to learn this.
Posted a little to soon, what you are saying Ozyluzi makes a lot of sense, although elements does not have the fade command under edit.
Message edited by author 2005-04-29 23:30:36. |
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04/29/2005 11:32:13 PM · #10 |
You are correct about the printing...actually, a lot of oversharpening is required for printing.
I don't think the sharpening on Red Hats is bad at all, but is more noticeable against the black shirt of the tuba player. To really see if you've oversharpened, you can greatly enlarge the image in your photo-editor after applying USM, say to 200% or 400%.
See my post above, if you haven't already. |
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04/29/2005 11:32:40 PM · #11 |
| Using a radius less than 1, say 0.8 or 0.5 for full size shots or even 0.3 for the 640 pixel shots, helps reduce the haloes. |
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04/29/2005 11:40:36 PM · #12 |
Thanks everyone for your input the comments here are great.
Although I do not have the fade unsharp mask command in elements I used the blur command under filter and it removed a lot of the halo on the fiddlers back without messing up the entire image/
Message edited by author 2005-04-29 23:47:07. |
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04/30/2005 12:02:07 AM · #13 |
| i've heard that sharpening should be done in lab color on the lightness channel. i was going to try the fade trick, but lightness mode isn't available in lab. at least not in photoshop 7. does sharpening in lab color make any difference? |
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04/30/2005 12:06:20 AM · #14 |
| Sharpening in LAB is a good idea if you want to avoid color artifacts when using USM. You do this by only sharpening the luminance channel and leaving the A&B channels alone. |
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04/30/2005 12:37:17 AM · #15 |
I recently attended a Photoshop seminar for a day with another friend and one of the things the man covered was USM. Now, what I'm about to tell you flies in the face of everything you've been taught but it works for me and you can try it, if you like it, great, if not, your choice.
First convert your image to LAB mode. In Photoshop 7, select Image, Mode, LAB Color. Then select the Lightness channel only because like Olyuzi said, you are sharpening the luminance channel and not the colors.
Now here is where it gets weird for some, but it really works for me.
Set your amount as high as it will go, 500% in Photoshop 7. Then set your Threshold no higher than 5, no lower than 2. I usually pick 4, then set your radius as high as you want it. When you do this, the halos will appear BIG TIME! I usually start around 2 and then work my way down slowly. Zoom in on one area where light and dark converge and a halo is showing up. Then slowly, using your down arrow key, lower the radius. You will see the halo slowly disappear and then suddenly it will *Poof* go away! That is your radius setting. Then adjust your amount bar to help eliminate any additional noise that was created. Again, take it down slowly with the cursor to a point you like then use the arrow keys to fine tune it.
Oh, and always do this VERY, VERY, VERY LAST! Then convert back to RBG mode, save as you like and badda bing, badda boom, you have a sharpened picture! :)
Deannda |
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04/30/2005 02:52:23 AM · #16 |
That's fascinating, deannda. I'm gonna give that a whirl. Meanwhile, here's something that works very well for me where the "correct" amount of sharpening overall produces halos in localized high-contrast areas, like where horizon meets sky:
Make a duplicate layer before USM, Name it "USM", and apply your sharpening to this layer. Then set the underneath layer as source layer for the history brush, blow up the magnification big time, and using the smallest brush that covers the halo paint out the halo itself to reveal the non-haloed underlayer. This can be simplified, if you can easily make a selection that's reasonably accurate, by making that selection and then turning the selection into a border, so the history brush only works within that narrow stripe.
Robt.
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04/30/2005 04:22:19 AM · #17 |
Deannda's approach will give excellent results. You can achieve the same thing by copying the image layer, sharpening that and then setting the blend mode to "luminance". This does the same thing with only sharpening the luminance and not the colours. It's also nice because it's a non-destructive edit. Your unedited original image layer is still there.
John
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04/30/2005 05:00:28 AM · #18 |
Originally posted by floyd:
Deannda's approach will give excellent results. You can achieve the same thing by copying the image layer, sharpening that and then setting the blend mode to "luminance". This does the same thing with only sharpening the luminance and not the colours. It's also nice because it's a non-destructive edit. Your unedited original image layer is still there.
John |
Yes, that works also. But it's not legal in basic editing, unfortunately.
Robt.
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04/30/2005 05:08:31 AM · #19 |
| what's the best way to do prints at different sizes? i know sharpening should be done after resizing. it would be ludicrous to have copies of all of your files at different print-sizes. is it best to do all the editing and save the file unsharpened at original size and then later sharpen depending on output size? or should the sharpened image be saved? |
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