Hakimi bin Halim

 The direction of light in photography is important: different angles of light produce different shadows, changing the appearance of your subject.  Light in photography may be diffuse or direct. Direct light, such as light from the noon sun, hits the subject from one direction. If you’re looking for high contrast between light and shadows, direct light is a good choice.

 On the other hand, diffuse light hits the subject from several directions. Florescent lighting is one example of diffuse light in photography. The loss of contrast that diffuse light produces mutes colors and softens the image.

 The shadow volume behind an object lit by an area light source (in contrast to a point light source) doesn't have sharp boundaries. This is caused by the fact that each point in the boundary area is only partially shadowed. The area (volume) in full shadow is the umbra, the boundary area the penumbra.

 It's useful to know a little about the inverse square law especially when using flash or studio lights.  Basically all the inverse square law says is that an object that is twice the distance from a point source of light will receive a quarter of the illumination.

 What it means to us photographers is that if you move your subject from 3 meters away to six meters away, you will need four times the amount of light for the same exposure.

 The reason why the power of the light diminishes so rapidly is not because it 'runs out of energy' or anything like that, but because it spreads and so a smaller and smaller proportion of the light hits the object. Here's a little diagram to illustrate the point.

 Inverse Square Law = 1/Distance2  ISL = 1/D2

 The Color Spectrum Both the natural light of the sun and artificial incandescent light appear white to the naked eye. However, if you shine light through a prism, it splits into a rainbow of colors. This effect shows how the “color” white contains every shade in the color spectrum.

 Color can only exist when three components are present: a viewer, an object, and light. Although pure white light is perceived as colorless, it actually contains all colors in the visible spectrum.  When white light hits an object, it selectively blocks some colors and reflects others; only the reflected colors contribute to the viewer's perception of color.

 Naked human eyes can only see the small magnitude of electromagnetic wavelength. Our eyes only can see the electromagnetic distance from 400nanometer to 700 nanometer  (1 nanometer (nm) = 1/1,000,000nm or 1 nm = 10 Angstrom)  Human eyes interprets 400nm to 700 nm as white light.

 The white light as interpret by our eyes divided into a range of distance  400nm to 450 nm = Violet  450 nm to 500 nm = Indigo / Blue  500nm to 580 nm = Blue / Green  580 nm – 600nm = Yellow  600nm – 650 nm = Orange  700nm = Red

 However, besides 400nm – 700nm, human eyes can also sense Ultraviolet (100nm) wave and Inflared (1 micron) wavelength. Tips = The short wavelength interpret by human eyes is Violet (400nm) while the longest wavelength is Red (700nm)

 It also travel in a straight lines.

 The radiation also brought the quantum energy known as Photons

 Primary color  Involve Blue, Green and Red. (RGB)  The mixture RGB colors with the same quantity will produce white color.

 Secondary Color  It engage Yellow, Magenta and Cyan (CMY)  The mixture of CMY with the same composition/amount will produce Black Color

 Complimentary Color  complementary colors tend to look balanced and are colors opposite to each other on the color wheel

 Virtually all our visible colors can be produced by utilizing some combination of the three primary colors, either by additive or subtractive processes.  Additive processes create color by adding light to a dark background, whereas subtractive processes use pigments or dyes to selectively block white light. A proper understanding of each of these processes creates the basis for understanding color reproduction.

 Red + Green → Yellow  Green + Blue → Cyan  Blue + Red → Magenta  Red + Green + Blue → White

 Cyan + Magenta → Blue  Magenta + Yellow → Red  Yellow + Cyan → Green  Cyan + Magenta + Yellow → Black

Opposite site of each color can be identify as a complimentary color. For example : Magenta is complementary to green color