A square region consisting of all possible hues (0 ≤ H ≤ 1) and lightnesses (0 ≤ L HSL ≤ 1), where all colors are fully saturated (S = 1), i.e., as saturated as they can be for the Lightness value. The most visually saturated colors occur where L HSL = 0.5. (The HSL subscript is used to distinguish it from CIELAB L.) L = 0 is pure black 1 is pure white. S = 0 for gray 1 for the most saturated colors for a given Lightness value. S = Saturation = max(R,G,B)/min(R,G,B).(0 to 6 is used in the Figures below for clarity.) H = Hue varies from 0 to 1 for the color range R → Y → G → C → B → M → R (horizontally across the image on the right).The test pattern, shown (reduced) on the right, was generated using the HSL color representation. Prints usually appear weak in the absence of truly deep black tones. Tonal quality is strongly correlated with Dmax- the deepest attainable black tone, as well as the tonal response curve. Best results are obtained by scanning it next to a step chart such as the Koda Q-13.Ĭolor quality is a function of gamut- the range of saturated colors a print can reproduce, as well as overall color response- the relationship between file pixels and print color. Scan it on a flatbed scanner, preferably one that has been profiled.Print the test pattern, noting (as applicable) the printer, paper, ink, working color space, ICC profile, rendering intent, color engine, and miscellaneous software settings.Assign a profile to the test pattern, if needed.The essential steps in running Print Test are You can observe response irregularities by viewing the test print, but you need to run Print Test to obtain detailed measurements of the print’s color and tonal response. Using a print of a test pattern scanned on a flatbed scanner. Dmax, the deepest printable black tone: a very important print quality factor,.Tonal response, the relation between pixels and print density, and.Color gamut, the range of saturated colors a print can reproduce, i.e., the limits of color response,.Color response, the relationship between pixels in the image file and colors in the print,.Imatest Print Test measures several of the key factors that contribute to photographic print quality, NOTE: Print Test will be deprecated in Imatest 5.2. Measure print quality factors: color response, tonal response, and Dmax
0 Comments
Leave a Reply. |