I was having a conversation recently with a fellow photographer and the discussion turned to taking the sharpest possible photos with your camera, and what was needed for it. Inevitably, post production came into play, and being very much a purist, he claimed that he does no sharpening in post production. It struck me that this sounded odd to run no sharpening algorithms in a digital world, as my understanding was quite different. I tried to make the case orally, but was hard-pressed to really make a convincing argument for it without supporting documentation. Given my penchant for writing, the resolution was my advice to “read the blog in a few days…there will be a post on sharpening”! So, for Paul (and for others who may be interested, here’s my take on whether or not to sharpen your images, and when!
The way I understand the digital photography landscape (no pun intended), is that there are three phases in which you can (and should) sharpen your images:
- Capture Sharpening – This type of sharpening is done on initial import from your camera to your image editor. Whether that is through ACR in Photoshop, in Lightroom (which has ACR built in), or any other application. This initial one is of utmost importance because of the inherent softening of images during the demosaic process when interpreting raw sensor data. As I understand it, the settings used here are relative to the camera you are using, but not so much the specific image.
- Creative Sharpening – After import, this would be the time when selective and subjective interpretations are done on images. Whether you choose to apply USM (unsharp mask) in Photoshop, a High Pass overlay layer, or some other means, these types of effects are always done to taste, and very much open to interpretation.
- Output Sharpening – Last, but not least, output sharpening is when you apply sharpening effects specific to your output device. These settings are dependent on the output device, such as a printer, the web (screen), as well as the size and resolution of the output image (smaller size requires less sharpening than larger files). Even within output sharpening there are settings specific to the printer you are using, and to the paper you are using,
Again though, these are just my impressions on whether sharpening is needed in a digital age or not. I know someone is going to ask, so should probably state here that an entirely different set of criteria should be used when talking about film sharpening techniques…but I digress! 🙂 Back on topic, there’s actually a couple really good resources (from my biased perspective of course) that discuss sharpening in much greater detail than I did here. First off, a book called “Real World Sharpening” by Bruce Fraser and Jeff Shewe is one I would highly recommend. For those with an online reading preference, here’s another good article on the subject, also by Bruce Fraser.
Am I off base? What are your thoughts on sharpening? Is it needed in a digital world? When and how do you sharpen your images (if at all)? Sound off in the newest poll (also in the sidebar):