180 likes | 355 Views
C O L O U R. Dr D Adriaens. What do we (not) see?. Which / how many colours do we see?. Red, Orange, Yellow, Green, Blue, Violet, ..., Jade, White, Black, Brown, Pink, Alizarin, Lavender, Amber, Maroon, Aquamarine, Beige, Turquoise, .
E N D
COLOUR Dr D Adriaens
What do we (not) see? Which / how many colours do we see? Red, Orange, Yellow, Green, Blue, Violet, ..., Jade, White, Black, Brown, Pink, Alizarin, Lavender, Amber, Maroon, Aquamarine, Beige, Turquoise, ... ...many. A computer nowadays ‘sees’ over 16 million colours. The exact number? 16,777,216 (for 24-bits images); up to 281,474,976,710,656 (for 48-bits images). A human eye can see about 10,000,000 different colours (of course, when you’re not colour blind...) ...and which / how many don’t we see? Let’s find out!!!
Metals: two (simultaneous) experiments... • Iron (Fe) can be different colours: • Silvery grey: iron metal (Fe0) • Green-yellow: iron oxalate (Fe2+) • Brown-red: blood cells, rust (Fe3+) • Blue: iron oxide (Fe2+ and Fe3+) • Can we change the colour in a simple experiment?
Metals: two (simultaneous) experiments... • Copper (Cu) can be different colours: • Bronze: copper metal • Black: copper oxide • Red: copper oxide (again) • Green: copper carbonate • Blue: copper sulphate • Can we change the colour in a simple experiment?
Metals: two (simultaneous) experiments... COPPER IRON Silvery grey Green-yellow Brown-red Blue • Bronze • Black • Red • Green • Blue
Iron Oxalate xxxxxxxxx xxxxxxxxx Fe(COO)2 2 CO2 Fe www.acdlabs.com: Chemsketch
Copper Oxide CuO or Cu2O CuSO4 H2 + ... www.acdlabs.com: Chemsketch
Copper Carbonate Imagine CuCO3 as CuO and CO2... www.acdlabs.com: Chemsketch
COLOURS Red: 700-635 Orange: 635-590 Yellow: 590-560 Green: 560-490 Blue: 490-450 Violet: 450-400 Red-Green Blue-Yellow Black-White
The webcam: an experiment... A webcam changes colours... ...into an electrical signal. USB cable – to computer CCD – captures light and changes it into electricity Filter – removes unwanted light Focusing lens – focuses the light to a smaller beam
The webcam: an experiment... The computer screen or the projector... ...changes this back into colour. A webcam changes colours... ...into an electrical signal. What if something goes wrong??
The webcam: an experiment... USB cable – to computer CCD – captures light and changes it into electricity Filter – removes unwanted light Filter – removes unwanted light The filter doesn’t work properly... Focusing lens – focuses the light to a smaller beam
COLOURS Infrared: > 700 Red: 700-635 Orange: 635-590 Yellow: 590-560 Green: 560-490 Blue: 490-450 Violet: 450-400 Ultraviolet: < 400
Now... How can we use it? BASES ACIDS (eggs, baking soda...) (lemon, vinegar, coke...)