Intro • SensorLensFocusExposureRecordingExamplesCompare

La Porte Rouge (the Red Door),
Langeais, France, 2005.
Canon PowerShot Pro1,
f/5.6, 1/200 sec.

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Photographic Image Quality

By “image quality,” I'm referring to the perceived sharpness, detail, contrast, and color rendition of the viewed image, whether on a computer screen or more importantly in a print. Others may think of this differently, and there are numerous aspects of image quality that can be physically measured in some way—for example, lens or print resolution—but what we see is what really matters to me.

Although post-processing and printing can dramatically affect the final result, no amount of digital magic can overcome flaws in the original out-of-the-camera file. Our goal here is to achieve the best possible quality in that file, within your own requirements for size, weight, cost, and usability.

Image quality is dependent on five basic factors:

  • The first two are completely dependent on the camera
    • Sensor
    • Lens
  • The second two are shared by the camera and the photographer
    • Focus
    • Exposure
  • The last is a camera capability selected by the photographer
    • Recording format

Each of these is discussed in the following pages.

I intended this paper to be a tutorial for some friends who are relatively new to photography, but it kind of grew on its own beyond that scope. In a way, this is a guide to buying and using a camera, but I’m not advocating any specific system or brand. In another way, it's a supplement to your camera's user manual, which will tell you how to set various functions but not why you would want to do so. I do hope that it will be helpful for anyone who is interested in going beyond “point and shoot,” whether their goal is travel photography, family activities, artistic image making, or just having fun with a camera.

Bias alert: I’m a still photographer interested in travel, nature, architecture, and social artifacts like trains and cars. Photographers with other interests will think about these topics very differently than I do. I’ve tried to convey factual information as simply and accurately as possible, but I’ve also included “consumer warnings” where appropriate.

Unlike blog sites, you’ll notice the absence of “click here to purchase online” links. In fact, I encourage you to buy from your local bricks-and-mortar camera store, which can provide the kind of personalized service that is impossible online and can only survive with our continued patronage. If you are in the Orange County (CA) area, visit my friends Barry Evans (pro gear), Ken Forbes (cameras) and Sarah Gregor (supplies) at Samy’s Camera in Santa Ana, on Bristol at Alton. (Samy’s also has stores in Los Angeles and Santa Barbara.)

Please also visit my own SmugMug photography site, my Blurb book listings, and the site of my photographic mentor (and web development client) Robert Hansen.

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