Sharpening images can be a great tool for drawing viewer focus and emphasizing texture. It’s also something that pretty much all photographs will need to do at one point in their lives.
The sensors and lenses of digital cameras always, more or less, blur an image and this requires correction. Image sharpening can be done with various tools, but no matter what tools you choose, you need to keep in mind that image sharpening needs to be done in moderations, otherwise sharpening artifacts will appear. When done properly, though, image sharpening can take an average picture and turn it into a spectacular one. Find out more in this brief guide to image sharpening.
The vast majority of image sharpening software tools do their magic by applying an unsharp mask, which actually sharpens an image. The gist of it all is that the tool works by exaggerating the brightness differences along the edges that exist within an image. Most of the sharpening setting in various image sharpening software are quite standardized. So, a person can usually adjust at least three main settings: radius, amount and threshold or masking.
Radius controls the size of the edges one wishes to enhance. Use a radius setting that is comparable to the size of the tiniest detail within your image.
Amount controls the overall strength of the sharpening effect and it is listed as a percentage in most cases. 100% if often a good starting point.
Threshold is the setting that controls the minimum brightness change that will be sharpened. It’s the number one setting that one needs to use in order to avoid sharpening noise.
As a general rule of thumb, it is recommended that one first optimizes the radius setting, then the amount and only then the threshold. As is generally the case, you may need to play around with the settings until you get the results you want.
Useful Image Sharpening Software Advice
Here are some bits of advice for image sharpening software:
- If there is one thing we recommend you remember before you start your journey into image sharpening is the fact that sharpening cannot be reversed and that you should always save the originals whenever you have the chance to do so.
- In case you didn’t know, RAW and TIFF files respond much better to image sharpening than regular JPEG files, because they preserve much more detail than the JPEG ones. Also, sharpening a JPEG file image, could amplify the compression artifacts of the JPEG.
- If you have an image that you want to sharpen and the blurriness of that image is due to subject motion or camera shake, then you will need to get into much more advanced techniques than the regular radius, amount or threshold. For example, you can use Photoshop’s smart sharpen.
- Did you know that some camera lenses do not blur people or objects equally? Just like the human eye, some camera lenses can suffer from astigmatism. This type of camera blur increases further from the center of the image and can go in a direction which is either perpendicular to that direction or away from the image’s center. If you’ve got an image like that on your hands, you’re in for some hard work, because these types of images require creative sharpening.
- A neat trick you can try to make images appear sharper is to, during RAW development, remove the chromatic aberrations. You can find this option in Adobe Camera RAW, under lens correction. You should know that almost all photo editing software these days will offer a similar feature. Use it!
- You should know that over sharpened images can be recovered (partially) in Photoshop by duplicating the layer, followed by an application of a Gaussian blur of 0.2-0.5 pixels to this layer 3-5 times and then setting the blending more of the top layer to darken and decreasing the opacity of the layer to reduce the effect.
- The light sharpening halos are more unpleasant than the dark halos.
- Learn when to stop. It can be very easy to let yourself get caught in the whirlpool that is sharpening images, but from time to time, just take a little break and move away from your laptop. This is the only way to get a new pair or fresh eyes that will help you in deciding when enough is enough.
Do you know of any image sharpening tips that you would like to share with us? Make sure you tell us in the comment section below or on our Facebook account!
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