Week 2 Tutorial
Please attempt the problems before the tutorial.
Question 1
You have a computer system with a colour monitor and printer.
a) The CIE chromaticity coordinates for the phosphors on the monitor are:
| Primary | x | y |
|---|---|---|
| red | 0.63 | 0.33 |
| green | 0.26 | 0.59 |
| blue | 0.15 | 0.06 |
Indicate on the CIE diagram below (from page 590 of the text) the range of colours that can be displayed on the monitor.
b) The CIE chromaticity coordinates for the inks used in the printer are:
| Primary | x | y |
|---|---|---|
| cyan | 0.17 | 0.25 |
| magenta | 0.40 | 0.24 |
| yellow | 0.46 | 0.51 |
Because mixing inks does not subtract colours perfectly, I also need to tell you the colours that result from mixing equal quantities of each ink colour:
| Combination | x | y |
|---|---|---|
| magenta + yellow | 0.58 | 0.37 |
| cyan + yellow | 0.27 | 0.57 |
| cyan + magenta | 0.19 | 0.12 |
Indicate on the CIE diagram the range of colours that can be produced on the printer.
c) What problems will arise when you try to print a picture produced on the screen?
Question 2
Polarized sunglasses block horizontally polarized light. This reduces glare because light reflected off flat surfaces like roads and water tends to be horizontally polarized. What happens if you look at an LCD display wearing polarized sunglasses?
Question 3
Here (from pages 594 and 597 of the text) are diagrams showing the RGB and HSV colour spaces.
| RGB colour space | HSV colour space |
|---|---|
 |
 |
Draw up a table showing corresponding RGB and HSV co-ordinates for black, white, red, yellow, green, cyan, blue, magenta, and brown (RGB (0.65,0.15,0.15)).