Monday, March 20, 2017

Assignment 8: Hue, Value and Chroma Charts

Schedule

Due Monday, March 20th- 
1" swatches for the following:
- Color wheel and corresponding achromatic grays
- Colors for psychological, historical, and subtractive primaries
-achromatic greys for new value scale (11 steps)

Due Wednesday, March 22nd- 
1" swatches rough-cut for the following:

  • 10-step chromatic scale in yellow (only chroma shifts, no shift in value or hue)
  • 10- step chromatic scale in violet (only chroma shifts, no shift in value or hue)
  • 11- step achromatic scale (no chroma, even steps in value based on chart)

Note: cut your swatches to 1" height, but leave the other sides longer. 

Due Monday, March 27th-
All of the following must be completed for start of class. Please bring rubber cement, xacto, blades, and ruler to class. You will be mounting in class. Must have the following 1" swatches COMPLETELY CUT AND READY TO MOUNT at the beginning of class:

  • 10-step chromatic scale in yellow
  • 10-step chromatic scale in violet
  • 10-step chromatic scale in blue
  • 10-step chromatic scale in orange
  • 10-step chromatic scale in green
  • 10-step chromatic scale in Red
  • 11-step Achromatic Gray Scale
  • 12 colors for color wheel
  • 12 achromatic grays that correspond to color wheel
  • 4 colors for psychological primaries (Red, Green, Yellow, Blue)
  • 3 colors for historical primaries (Red, Yellow, Blue)
  • 3 colors for subtractive primaries (Magenta, Yellow, Cyan)
Due Wednesday, March 29th- 
FINAL CRITIQUE- Everything Mounted and ready for presentation.








From David Briggs website

"Mixing with grey is commonly also accompanied by a shift in hue (Fig. 6.3.3B), generally in the same direction as that seen in mixing with white paint. These shifts are accentuated if the grey is somewhat bluish, as results from mixing most black paints with white. A perfectly neutral grey (made for example using raw umber plus a black as the darkener) will eliminate this latter component of the shifts, but not the hue shifts that are due to the undertones of the coloured paints. Using a grey to reduce chroma is an important tool that keeps the painter in control of the value of the mixture, whereas the traditional recipe of mixing with the complementary tends to surrender control of the value to the paint.

Adding black paint alone to a paint mixture typically reduces saturation as well as chroma and value, and thus yields shadow colours that are too low in chroma to be correctly related to the lights. Strongly coloured objects remain at high saturation even at their lowest values, which may need to be painted using a very high proportion of colourant; pure black paint, being a very low value neutral (grey), is unsuited to represent the lowest values of such objects.

Darkening with black may also cause a hue shift that needs correction, but this problem occurs with any darkener. The main shifts are red > purple, and orange > yellow> green, both of which can be corrected by dragging the hue back with a trace of a strong orange or scarlet colorant."








From David Briggs website:

"Ideal yellowmagenta and cyan colorants would be the optimal primaries for paint mixing, if such pigments existed. However, even today our best magenta and cyan pigments are well towards red and blue respectively, compared to the ideal magenta and cyan subtractive primaries. No high-chroma pigments are very close to an ideal magenta hue.


The closest high-chroma oil painting pigment is quinacridone magenta (PV 19), which is distinctly redder than ideal magenta. 

The closest popular oil painting pigment to an ideal cyan is the green shade variant of phthalocyanine blue (PB 15.3), which similarly is distinctly bluer than an ideal cyan. 

Note: Cobalt green is closer to ideal cyan in hue, and does mix some blue-green colors not obtained using phthalocyanine blue alone as the primary, but yields fewer colors in the bluish range. It is also more expensive, and being opaque is less suited to mixing dark colors. 

Yellow pigments are available in an essentially continuous range of hues, and a pale or lemon yellow seems to provide the optimal gamut of colors."

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