Nicole Atterberry:Digital Graphics: GIMP: Chapter 8: Color

Name:

Nicole Atterberrry

Student Number:

X00105576

GIMP: Chapter 8: Color

PART 1: READ Chapter 2 in the GIMP book, then:

Answer all questions below, briefly but completely.
Change the color of the answer to BLUE.
Copy this information and paste in a new post in your DIGITAL GRAPHICS blog.

1. Briefly define the following color terms:

· Additive color: A technique that uses 3 pixels in 3 colors of red, green and blue lights, to combine into any almost any color.

· Subtractive color: Is adding shades of paint to reflecting surfaces, in which creates a darker image.

· HSV color: Hue, Saturation, Value; uses 3 numbers on a scale to represent colors. Hue measures where the color falls in spectrum 0-360, Saturation represents how intense color is 0-100, and Value represents how bright pixel is 0-100.

· CMYK color: Used on professional equipment for “print media” allows control over how much black get into the image.

2. What is the relationship between additive and subtractive color? They are exact opposites of each other; mixing two additive primaries gives your one of the subtractive primaries and vs. versa, mixing two subtractive primaries gives one of the additive primaries.

3. How many bits do most computers use to represent color? 24 –bit (8 bit per channel) Modern computers use 32 –bit.

See the Important Note below regarding bit color.

4. What is the TRIANGLE COLOR SELECTOR used for? Used as an alternative to the vertical slider on the HSV interface, in which you drag points on the triangle to adjust saturation and value.

5. What is the TRIANGLE COLOR SELECTOR used for? Used as an alternative to the vertical slider on the HSV interface, in which you drag points on the triangle to adjust saturation and value.

IMPORTANT NOTE:

In GIMP, the bit break-down is:

· RGB Channel: 8 bits for RED, 8 bit for GREEN, 8 bits for BLUE

· ALPHA Channel: 8 bits for TRANSPARENCY

About TRANSPARENCY :

An Alpha value indicates the transparency of a pixel. Besides its Red, Green and Blue values, a pixel has an alpha value. The smaller the alpha value of a pixel, the more visible the colors below it [the greater the transparency]. A pixel with an alpha value of 0 is completely transparent. A pixel with an alpha value of 255 (or Hex ff) is fully opaque.

With some image file formats, you can only specify that a pixel is completely transparent or completely opaque [JPGs are always opaque]. Other file formats allow a variable level of transparency [such as GIF and PNG].

From the GIMP Glossary: http://docs.gimp.org/en/glossary.html

PART 2: GIMP PROJECT:

1. HEX Web Colors: Go to this link to find more about web colors: http://en.wikipedia.org/wiki/Web_colors

From the information in this Wiki article, analyze the following hex values and describe what color of each (the first is done for you):

A. #cc22cc Color: purple (Notice the high RED and high BLUE values)

B. #ff0000 Color: Red (high red)

C. #0000bb Color: Blue (high blue)

D. #000000 Color: Black (zero red, blue and green)

E. #11ff11 Color: Green (high green, low red and blue)

F. #999999 Color: Gray (What color is it when all the hex digits are the same?)

2. HEX Web Colors Image:

· Now open GIMP and create a new 600 X 600 art canvas.

· Choose the BRUSH Tool.

· Click on the Foreground Color Picker at the bottom of the Toolbox and type in the first color (#cc22cc) from the list above.

· Use a calligraphic brush to draw out the word PURPLE across the canvas. See the sample here à

· Create a new layer.

· Now enter the second color above (#ff0000) in the Color Picker, and draw out the appropriate color word with the Brush on the new layer.

· Continue adding new layers with the appropriate color names for each of the colors above. (The color words can overlap, be at angles, be different sizes, different transparencies, etc. You can also add brush decorations, shapes, etc. if you like to create an interesting, attractive image.)

· Save the image as a JPG in your GIMP folder with the file name Hex Colors

· Delete the sample image (“Purple”) and insert your own Hex Colors image here:

3. Color Adjustments:

· Go to the web site for this book: http://gimpbook.com

· Click on the PHOTOS FROM THE BOOK link, and scroll down to see the images for Chapter 2.

· Download and save these images: Yosemite Storm, the yellow flower, Dave (image of man at a table, right after the yellow flower image), and the Shakespeare page.

· With the images you downloaded, follow the instructions in pages 303 through 319 to adjust various color properties. You do not have to complete the entire chapter; you may stop just before Indexed Color on page 219. (Of course, you are more than welcome to complete the chapter if you like.)

· After the adjustments, save the final version of the images, then insert the final adjusted images here:

Yosemite Storm: