Photoshop sharpening überbasics- in *English*?

Biggles

Biggles

My cup runneth amok.
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I've been trying to get an acceptable result by unsharp-masking a scanned black & white silver print in Photoshop LE. Going nowhere fast. The basic picture has pin-sharp elements, but I can't seem to make them look anything but blurry on my screen. (I have the manual, but I simply cannot understand it. It's not written in any known language.)

However, I never had any real trouble sharpening the several thousand digital camera pictures I took from 2002-2004. Trouble is, I changed screens in 2004, and my new screen just doesn't seem to need as much sharpening, so I basically stopped doing it. My digital camera pictures look just fine as-saved. Can't remember what my typical sharpening setpoints were. Trying random settings is just making me... angry.

Apart from the fact that I now have no idea where to put my initial settings, I have no idea if I should use the same base settings for pure digital pictures as for digital files of scanned paper prints.

Where should I start? (And please type slowly and use firm pressure on the keys; I am a pretty dumb bunny when it comes to digispeak.)

Any help will be appreciated.
 
spooky...those are my default starting points too!! like exactly! that works for screen based images, but if you are working w/ higher res (to print)...you will need to change those a bit, and increase the radius (and generally decrease the amount).
 
nksyoon said:
How about amount=150%, radius=0.3 and threshold=0?
Click to expand...
Good starting points.
Bear in mind that sharpening usually needs to be adjusted to output. The optimum may be quite different between screen and print (or even between screens with different pixel pitch, AFAIK).
If you are starting from a sharp original, you may need less than the above. The inverse is also true.
One measure which might help is to play about with increasing radius and/or amount until you see artifacts like white halos, then back off somewhat.
Try increasing threshold for faces you don;t want to look too grizzly, i.e. mainly for the ladies.
 
For web output, eg 600x400 to 900x600, from my Canon 20D I use a radius of 0.3 and amount between 75%-150%.

For A4 inkjet output from my Canon 20D I use a radius of 0.5-0.6 and amount between 150%-200%. Screen viewing at 50% to gauge amount of USM needed.

I haven't done any home printing from normal 35mm, but I have printed 19cmx52cm (approx) panoramas from my Xpan. These were scanned at 4800dpi on an Epson 4990 and sharpened with radius 0.6 and amount 300%. Film was HP5+ and NPH400.
 
Here's a better starting point: Set radius at PPI divided by 100, do not change radius unless PPI changes. Start with amount at 120 and threshold at 7. Remember to view at 100%!
 
i mostly scan prints at 300ppi and found that best radius is around 3, so i guess that fits the above advice... Amount...around 100, but sometimes a second round with about 50 is needed. Treshold...usually a bit lower, like, 3-4, but that depends on the tonality of the image. If there's smooth gradation like sky or such, i give some higher treshold.
 
Thank you all VERY much. I'll give those a bash.

For the record, I'll be scanning traditional black & white paper prints in sizes from 4x6 to 11x14, strictly to post on the Internet. My test print, the one I'm bitching about, is a 4x6 Ilford postcard I scanned at both 300 and 900 pixel-per-inch resolution, saved as TIF.
 
900?? oh uh, are you sure your flatbed can handle that? many of them just interpolate resolutions and that does not help the sharpness.
 
600 PPI, even 900 PPI isn't too much to ask from a flatbed scanner, unless it's an old one. The epson flatbeds can probably do at least 1500. 2000 PPI seems to be the sweet res for my 4180. But I'm scanning negatives, not postcards - 600 PPI when your paper is 5x7" yields pretty big files that might not be terribly fun to edit depending on your computer hardware.

But that's neither here nor there. I just wanted to say that USM is something you might consider applying more than once to the image, with different radii, and the bulk of the sharpening should happen before you down-res the image for posting on the web. I do two-step sharpening on my neg scans: first with a larger radius (between .8 and 1.2 for my 2000 PPI scans of 35mm) to define general areas of detail, i.e. the outline of somebody's face and eyelashes, and then I do a second sharpening at about half the radius to resolve the grain.

Rarely do I sharpen again after shrinking down to web res, but .2 to .3 at anything up to 500% is good for web images. Note that sharpening doesn't gain you any detail whatsoever, it just enhances micro-contrast to make your image look snappier. When overdone, it causes haloes and aliassing (aka "jaggies") in diagonal lines.

Beware of the Threshhold parameter, it yields some truly gross looking artifacts in the noise or grain of your images.
 
FWIW I scan a large initial file to give me a 16X24 print size at 300dpi, so my USM may be too much on smaller file sizes. I use USM at Amount 120/Radius 2.8/Threshold 3 and then do a second pass at A 20/R 50/T 0. Generally I do not have to do more USM on the same file when it is resized downward. As with everything your mileage may vary. I use PSE 2.0 and do not find the Help section vary useful either.

Bob
 
A few supplementary notes. Apply USM as the last edit. Zoom the image to 100%—actual size—before applying USM. My default settings are 20, 10, 0.

Possibly your scanner/scanning is the source of your problem. Using APS LE indicates that you may have an older scanner which might not be doing the job for you. The attached target is useful for understanding the effects of USM settings. Apply USM to the target, then zoom up to see the effects...skip
 
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