Sharpening for Print

 

buffalocity

Print making is quickly becoming a lost art form. It is a subject that could fill volumes of  books. Sharpening is one of the most  often misunderstood tool in the photographers palette. I often hear about  and photographers who try to use unsharp mask to sharpen an image that was poorly taken and is blurred for some reason. I have come to the belief that is an effort in futility  If you miss focus, or camera shake has blurred an image, it probably can not be “fixed” by post sharpening. In fact, the best case senario for such an image is it will appear slightly less blurry, while the levels of noise in the image will become very noticeable.
One use for sharpening is getting the best possible file for print. I usually apply what is called a high-pass method sharpening to my images. The reason the High Pass filter technique works so well at sharpening images is because any areas in the image which are not an edge are left untouched. The only areas that have sharpening applied to them are the edges, which is exactly what you want, and also what all of those confusing options in the “Unsharp Mask” and “Smart Sharpen” filters are trying to help you achieve.

How to use High Pass Sharpen:

  1. Open your image
  2. ctrl+j to duplicate layer
  3. change the layer blending mode to overlay
  4. filer > other > high pass
  5. set the radius slider to 2.1 (i usually start at 2.1 and go from there)
  6. Flatten layers

You can also try “soft light” rather than “overlay” on the blending mode. A higher radius setting will add more sharpness to your images but at the cost of halos. I have found that for a 16×20 a radius of 2-3 works well for images from my 5d. I am testing my 6d now ( i am thinking that I will need less sharping than the 5d) For an 8×10, I would us less, a 20×30 would use a little more. The paper choice you use also changes the level of sharpening. Canvas prints will use more sharpening than gloss. The key here is to test on what you print.

You can download a copy of my high pass sharpening action for photoshop here. hi pass.atn

 

Edited image before sharpening:

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100% Crop before sharpening:

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100% Crop After sharpening:

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Sharpening Effect can be reduced if you lower the opacity of the high pass sharpening layer:

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