Sharpening Pictures

I messed something up yesterday, so I am going to try and turn it into a teachable moment.

I posted a mystery picture that looks fine but could look better. Right click on the link and open it in a new tab. Here is the same picture looking a little better; right click on the picture and open it in a new tab, too.

Now, click back and forth between the two tabs with the different pictures and see if you can see the difference. Today's picture looks a little better, a little more crisp; let's call it a little more sharp. Can't see the difference? Check out the tree leaves as you jump back and forth between the tabs; see how they pop into focus and are less blurry? Or, the pattern on Annette's dress? Once you get used to seeing it, everything looks a little more sharp.

What I forgot to do to yesterday's picture, which I corrected on today's picture, is to use the "sharpen" tool in Photoshop after I shrank the picture down to viewing size. Some programs, including Photoshop, call it "unsharpen mask". Sharpening increases the contrast between closely located pixels in an image, making their edges look more distinct. Many programs allow sophisticated adjustments of the sharpening process, which will yield vastly different results. Or, you can do as I did here and use the software's automatic sharpening function.

Wikipedia has a good article on the process.

Oversharpening an image will make it look anywhere between weird and bad. It is always better to not sharpen or undersharpen an original image, since you can always apply the sharpening process to a copy (don't mess up the original!) later in Photoshop or whatever program you use.