Why is Images so Important Conveying Information?
Writing in the Margins
Understanding image histograms is probably the single most important concept to become familiar with when working with pictures from a digital camera. A histogram can tell you whether or not your image has been properly exposed, whether the lighting is harsh or flat, and what adjustments will work best. It will not only improve your skills on the computer, but as a photographer as well.
Each pixel in an image has a color which has been produced by some combination of the primary colors red, green, and blue (RGB). Each of these colors can have a brightness value ranging from 0 to 255 for a digital image with a bit depth of 8-bits. A RGB histogram results when the computer scans through each of these RGB brightness values and counts how many are at each level from 0 through 255. Other …show more content…
Some image are examples which contain a very broad tonal range, with markers to illustrate where regions in the scene map to brightness levels on the histogram. This coastal scene contains very few midtones, but does have plentiful shadow and highlight regions in the lower left and upper right of the image, respectively. This translates into a histogram which has a high pixel count on both the far left and right-hand sides.
Lighting is often not as extreme as the last example. Conditions of ordinary and even lighting, when combined with a properly exposed subject, will usually produce a histogram which peaks in the center, gradually tapering off into the shadows and highlights. With the exception of the direct sunlight reflecting off the top of the building and off some windows, the boat scene to the right is quite evenly lit. Most cameras will have no trouble automatically reproducing an image which has a
Writing in the Margins
Understanding image histograms is probably the single most important concept to become familiar with when working with pictures from a digital camera. A histogram can tell you whether or not your image has been properly exposed, whether the lighting is harsh or flat, and what adjustments will work best. It will not only improve your skills on the computer, but as a photographer as well.
Each pixel in an image has a color which has been produced by some combination of the primary colors red, green, and blue (RGB). Each of these colors can have a brightness value ranging from 0 to 255 for a digital image with a bit depth of 8-bits. A RGB histogram results when the computer scans through each of these RGB brightness values and counts how many are at each level from 0 through 255. Other …show more content…
Some image are examples which contain a very broad tonal range, with markers to illustrate where regions in the scene map to brightness levels on the histogram. This coastal scene contains very few midtones, but does have plentiful shadow and highlight regions in the lower left and upper right of the image, respectively. This translates into a histogram which has a high pixel count on both the far left and right-hand sides.
Lighting is often not as extreme as the last example. Conditions of ordinary and even lighting, when combined with a properly exposed subject, will usually produce a histogram which peaks in the center, gradually tapering off into the shadows and highlights. With the exception of the direct sunlight reflecting off the top of the building and off some windows, the boat scene to the right is quite evenly lit. Most cameras will have no trouble automatically reproducing an image which has a