Question about sharpening in Photoshop or Lightroom...

[splproductions]

You know how when you sharpen in Photoshop or Lightroom, and you zoom in 1:1, you can see the little pixels around the edges of things? I.e., it's obvious that the computer added those pixels and that it wasn't in the original photo? Will those be visible when the photo is printed? I'm just trying to figure out how much sharpening I can get away with without it showing up.

 

[Ysarex]

It depends on how big you make the print and on what you make the print and how the print is viewed.

Joe

 

[MLeeK]

You should never do your final sharpen until you know what size you are printing. Your LR sharpening should only be a raw sharpening. Kind of a de-fogging sharpen.
When you do your final sharpen it should be after you have cropped to the print size and you should be at somewhere between about 60% and 100% view.
What you see is what you will get-roughly. LOL! Prints are not viewed from right on top of them, so your perspective is usually less than 100%.

 

[KmH]

No, those are not likely pixels added by the computer. The original photo is made of pixels. The only way to tell if those will be visible in a print is by determining what the print resolution will be.

If you are looking at a photo at 100% (1:1) and you are seeing jagged edges, you either cropped way to much, or it's a JPEG image and what you are seeing is MCU's (Multiple Coded Units), not pixels.

MCU's are 8x8, 8x16 or 16x16 pixels squares made when a photo is converted to JPEG..

Image sharpening is a fairly complex subject.

The goal is to control edge halos. Part of that control has to do with the frequency of the image that will be sharpened.

The photo of a stand of leafy decidiuos trees would be a high ffrequency image wil require much different sharpening techniques/settings than a low frequency head and shoulders portrait of a flawless skinned high school senior girl.

ACR (Lightroom/Camera Raw) can only do 'capture' sharpening. Photoshop has the tools, features, and functions needed to do the wide range of techniques used for 'local' and 'output' sharpening.

if you don't have it already, get the book written by the guys that wrote the sharpening program used in ACR 6/ACR 7 (CS5 Camera Raw/Lightroom 3/4) - Real World Image Sharpening with Adobe Photoshop, Camera Raw, and Lightroom (2nd Edition)

 

[Big Mike]

As mentioned, there are different types/times to do apply sharpening. There is capture sharpening, which is typically what is applied in ACR or Lightroom. But there is also output sharpening, which should be done with your intended output in mind.

So in LR, when you export, you can choose the output sharpening that you want. The options are 'Screen', 'Print Glossy' & 'Print Matte'...and then you have low, regular, and high.

 

[KmH]

Which are all pretty crude adjustments offering little in the way of fine control.

 

[Big Mike]

Which are all pretty crude adjustments offering little in the way of fine control.

Yes, but there are some pretty smart things going on. As you mentioned, the sharpening algorithms were written by the experts who wrote 'Real World Sharpening'.