3. Color theory
Isaac Newton (Woolsthorpe-by-Colsterworth,
25 dicembre 1642 – Londra, 20 marzo 1727)
Johann Wolfgang von Goethe
(28 August 1749 Frankfurt a. M.-22 März 1832 in Weimar)
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5. White and monochrome light
In optics, a prism is a
transparent optical
element with flat, polished
surfaces that refract light.
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7. Speed of light…
Medium
Speed Km/s
299,792
Glass
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300,000
Air
Hendrik Lorentz (right) with Albert Einstein.
Vacuum
200,000
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12. Color mixing
• When we mix colors we see a new color!
• ADDITIVE is mixing lights
• SUBTRACTIVE is mixing color pigments
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13. Aditive primary colors: red, green, blue
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21. • Complementary
colors are pairs of
colors which, when
combined in the right
proportions, produce
white or black.
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22. Describin
g a color
• Hue
• Saturation
• Lightness
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36. Image file format: raster aka bitmap
• In computer graphics, a
raster graphics image, or
bitmap, is a dot matrix data
structure representing a
generally rectangular grid of
pixels, or points of color,
viewable via a monitor,
paper, or other display
medium. Raster images are
stored in image files with
varying formats
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37. TIFF
• TIFF is good for any type of bitmap (pixel-based)
images.
• TIFF produces large files, but there is no loss in
quality. TIFF also preserves layers, alpha
transparency, and other special features when saved
from Photoshop.
• The type of extra information stored with TIFF files
varies in different Photoshop versions, so consult
Photoshop's help for more information.
http://graphicssoft.about.com/od/graphicformats/f/summary.htm
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38. PNG
• Use PNG when you need smaller file sizes with
no loss in quality.
• PNG files are usually smaller than TIFFs, in my
experience.
• PNG also supports alpha transparency (soft
edges) and was developed to be a Web
graphics replacement for GIF.
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39. GIF
• Use GIF for simple Web graphics having limited
colors.
• GIF files are always reduced to 256 unique colors
or less and they make very small, fast-loading
graphics for the Web.
• GIF is great for Web buttons, charts or diagrams,
cartoon-like drawing, banners, and text
headings.
• GIF is also used for small, compact Web
animations. GIF should rarely be used for photos.
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40. Image file format: vector
• Vector graphics is the use of
geometrical primitives such
as points, lines, curves, and
shapes or polygon(s), which
are all based on
mathematical expressions,
to represent images in
computer graphics.
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