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Tutorials – Color Perception

Tutorials – Color Perception
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. The human eye senses this spectrum using a combination of rod and cone cells for vision. Rod cells are better for low-light vision, but can only sense the intensity of light, whereas while cone cells can also discern color, they function best in bright light. Three types of cone cells exist in your eye, with each being more sensitive to either short (S), medium (M), or long (L) wavelength light. Raw data courtesy of the Colour and Vision Research Laboratories (CVRL), UCL. Note how each type of cell does not just sense one color, but instead has varying degrees of sensitivity across a broad range of wavelengths. Additive Subtractive

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Discussing How to calibrate your camera and adapter in M42 Lenses and DSLR's headlights2 says: When you did buy an adapter you will need to perform two tasks 1: Calibration of the viewfinder diopter 2: Shimming the adapter. When done you will be much and much happier with your manual lens [ Shot with EOS 30D 55 mm SMC takumar f. 1.8 + 20 mm extension tube, @ f 5.6. Handheld focused at the bottum of the txt.

15 styles of Distorted Thinking 15 styles of Distorted Thinking Filtering: You take the negative details and magnify them while filtering out all positive aspects of a situation. Polarized Thinking: Things are black or white, good or bad. color basics The world is full of colors. Some researchers report that humans can distinguish about 16 million different colors. But what's more interesting is that most of the colors we see around us and all the colors we see on a TV or computer monitor can be created from just three different colored lights. How are all the colors made from just three different colors? Simply by combining the light in different ratios. That's it. A Flexible Depth of Field Calculator A depth of field calculator is a useful photographic tool for assessing what camera settings are required to achieve a desired level of sharpness. For a background on what everything here means, also see the tutorial on depth of field. Note: CF = "crop factor" (commonly referred to as the focal length multiplier) In order to calculate the depth of field, one needs to first decide on what will be considered acceptably sharp.

5 examples of how the languages we speak can affect the way we think Keith Chen (TED Talk: Could your language affect your ability to save money?) might be an economist, but he wants to talk about language. For instance, he points out, in Chinese, saying “this is my uncle” is not as straightforward as you might think. color theory Color Space Fundamentals Computer monitors emit color as RGB (red, green, blue) light. Although all colors of the visible spectrum can be produced by merging red, green and blue light, monitors are capable of displaying only a limited gamut (i.e., range) of the visible spectrum. Whereas monitors emit light, inked paper absorbs or reflects specific wavelengths. Cyan, magenta and yellow pigments serve as filters, subtracting varying degrees of red, green and blue from white light to produce a selective gamut of spectral colors. Like monitors, printing inks also produce a color gamut that is only a subset of the visible spectrum, although the range is not the same for both.

Understanding Your Camera’s Hyperfocal Distance Focusing your camera at the hyperfocal distance ensures maximum sharpness from half this distance all the way to infinity. The hyperfocal distance is particularly useful in landscape photography, and will help you make the most of your the depth of field — thereby producing a more detailed final print. However, knowing the hyperfocal distance for a given focal length and aperture can be tricky; this tutorial explains how it is calculated, clears up common misconceptions, and provides a hyperfocal chart calculator. Front Focus Back Focus Front-Center Focus

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