The dynamic range of any sensor used in digital cameras is defined by the largest possible signal divided by the smallest possible signal it can generate. The largest signal represents the maximum amount of light that can be converted by the sensor into a unique digital value that represents a pixel into a photo. The [...]
Posts Tagged ‘sensor’
Sensor Sizes
November 11th, 2010 
Andrei If we compare a typical sensor size to a 35 mm film, we realize that the sensor size of digital SLRs is typically 40% to 100% of the surface of the 35 mm film. Although they have similar number of pixels, digital cameras have smaller sensors. As a result, the pixels are smaller and the [...]
Sensors linearity
November 8th, 2010 Andrei Sensors are linear devices. If you double the amount of light, the sensor output will double, as long as the pixels are not full. If a pixel reaches full capacity, the output will be constant or clipped. Human vision is non-linear. If we double the light, the effect will be larger in low light conditions [...]
Sensors
November 4th, 2010 Andrei Inside our eyes there are cone-shaped cells, which are sensitive to some colors, called “primary colors”: red, green and blue. The other colors that we perceive are just combinations of these primary colors. In photography, the red, green and blue corespondents of light expose the corresponding chemical layers of color film. The Foveon sensors work [...]
Pixel Quality
November 1st, 2010 Andrei In digital photography, when we hear the expression “more megapixels” we tend to believe that “more is better”. But in this case “more” doesn’t necessary mean “better”. The photography quality depends on a multitude of factors, the number of pixels being just one of them. Each pixel value has a quality that can be described [...]
Pixels
October 28th, 2010 Andrei To understand the term of digital sensors we have to imagine an array of buckets collecting rain water. Digital sensors work the same way buy they consist of an array of pixels collecting photons, the minute energy packets of which light consists. The light sensitive photodiode converts the number of photons collected in each pixel [...]
Micro lenses
October 25th, 2010 Andrei Microlensses are usually placed on top of the color filter array on certain sensors of digital cameras, their principal role being to overcome the limitation of a low fill factor. Microlenses are also used in order to funnel the photons of a larger area into a smaller area of light sensitive photodiode. Microlenses are small [...]
AD Converter
January 17th, 2010 Andrei Sensors from your digital camera consists of millions of pixels with photodiodes which convert the energy from the light (actually from the incoming phototns) into an electrical charge. That electrical charge is then converted to a voltage which is amplified to a higher level so that it can be further processed by the ADC (Analog [...]
Lesson 15: Rule Of Thirds
November 3rd, 2009 Andrei The rule of thirds is one of the most basic composition guidelines in photography. The rule of thirds makes use of a natural tendency of the human eye to be more strongly drawn towards certain parts of an image. The rule states that an image should be imagined as divided into nine equal parts by [...]
Posted in Beginner's Tutorial 
Tags: composition, rule of third, rule of thirds, sensor, the beginning 
3 Comments »Lesson 7: ISO
October 17th, 2009 Andrei Digital cameras have an ISO rating indicating their level of sensitivity to light. The normal setting for most cameras is ISO 100, although some go as low as ISO 50. The sensitivities can be increased to 200, 400, 800, or even 3,200. High-end digital SLRs also allow some intermediary values. When increasing the sensitivity, the [...]
