Research into Cameras and Camera Science

I have created this post in the hopes to finally not need to ask any questions on camera sciences and camera practice. It will be a guide for me to look back on and a way of better obtaining new information I may come across so that it is fully understood and made possible to put into practice.

DSLR
A DSLR or SLR stands for Digital Single Lens Reflex. A single lens in commonly seen in digital cameras as they can rely on a single lens for viewing and shooting which opposes the Twin Lens Reflex (TLR) seen from film.
The idea is that an image enters a single lens which is then reflecting off of a mirror or prism to both see an images coming through the eye piece and capture it to the image sensor.

TLR
A ‘Twin Lens Reflex’ are two lenses of the same focal length commonly seen in film cameras. It relies on two lens systems: One acts as the ‘taking lens’ (the lens that takes the picture) and the other for the view finder system, usually an eye piece seen at waist level.

Mega Pixel Resolution
Pixels refer to ‘picture element’. It is said there are 1 million pixels to a picture element.
Resolution is often used for a pixel count in digital imaging. It is a calculation that is not entirely true; where the pixels resolution is summed up using integer numbers (true numbers without any fractions or decimal points) where the first number represents the pixel columns (width) and the second is the number of rows (height). For example 720 x 1080 or 720 by 1080.
Other conventions include counting pixels by length unit or pixel per area, such as pixel per inch.
This calculation is not favoured in American, Japanese and International standards and should not be used for the digital field.

According to the same standards we should only take into account of effective pixels i.e. the pixels that are obtained and produced into the final image. This is because many pixels like shielded pixels or ones that do not contain red, blue or green will not be picked up by the image sensor and therefore not count towards how many pixels are in the final picture.

Finally an image with a 2048 by 1536 has a total of 3,145,728 pixels or 3.1 mega pixels. You simply times both numbers together: 2048 x 1536 = 3,145,728.

Light Measurements
Light is calculated in a number of ways this is because the science can act differently depending on the calculation achieved i.e. how much light is given from a light or how much light is reflected off of a surface. There are key principles for each which is why calculate in necessary.
1) Velocity of Light (colour i.e. light intensity) – Wave Length x Frequency (Metres x Hertz)
2) Perceiving Colour – Observers sensitivity to Short, Medium and Long ‘Wave Lengths’
3) Photometry – Physical measurement of visible light VS Attributes of eyes and units of power:

  • Radiometric Quantity – Radiance (measurement of visible light)
  • CIE Standard Luminosity Function – Luminance and Illuminance  perceived by eye

4) Photmetry terms – Radiant Flux; Watt; Radiant Intensity; W / sr; Irradiance; W / m2; Radiance; W/m2/sr
5) Radiometry – Science and measurement of energy or electromagnetic radiation
6) Radiometry terms – Luminous Flux; Lumen; Luminous Intensity; Lm / sr = candela (cd); Illuminance; lm / m2 = lx; lm / ft2 = footcandle (fc); Luminance; lm / m2 / sr = cd / m2 = Nit;
lm / ft2 / sr = cd / ft2 = Fl
7) Inverse square law (lights into fractions over distance) – 1 metre distance = 1/4 lumen
8)

The light – Measurement of both radius and surface area of a light beam travelling inside a bulb
Power of light – Meaning the the energy into and given out from the light
Travelling light – Intensity of light travelling to a subject
Reflected light – The measurement of reflected light on a subject
Light laws – Distance, power, loss, perception,

http://www.ies.org/pdf/education/IES-Color-3-Webcast-Handout.pdf

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