Key Camera Specifications Explained
Key Specifications to Remember
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Introduction
There are many physical characteristics that are essential to the way in which a camera operates but most can be set aside except for a couple of them that have direct impact on image quality and usability. It is important to note that explanations are aimed at a beginner to intermediate level of knowledge pertaining to photography.
Image Sensors
Image Sensors are the single most important component in the entire camera, no matter the type of equipment that incorporates them. These components evolve slowly over decades as various approaches improve the initial performance of a particular design. Changes over a decade are slower than release cycles of products that incorporate them. In order for manufacturers to promote their products as improved designs, they must rely on other aspects to achieve differentiation.
Cameras that incorporate sensors have their own requirements in terms of size, cost and power usage. This means that a design that works well in a large camera is ill suited for a small one. Phones in particular require the most compact image sensors that have low power requirements and are also affordable enough for a manufacturer. The size requirement is the most important reason for the compromises that that a phone has in terms of image quality. It is very hard to reach a good enough result.
Some configuration details may not be disclosed about product manufacturers since they consider them to be a commercial secret.
Colour abilities
A colour image sensor, as almost all cameras have and advertise, is a compromise in itself. Any filter through which light passes, and particularly small ones, are more prone to consistency issues and poorer image quality. As the image is split into the R(ed), G(reen) and B(lue) primaries, the image has less brightness and contrast. Most cameras actually have a pattern of light sensitive cells that may mean that more detectors are devised for luminance than colour information
Larger, professional cameras may have 3 separate sensors, each being used only to capture a particular color, such as red, green and blue. These products have the advantage of being marketed to a public that is willing to pay more for specific features. Such an ability actually offers at least three times the accuracy of images being captured, making sure that colors never bleed on adjacent areas and contrast is not compromised.
Rarely more than a passing mention about the sensor features is present. Unless otherwise specified, almost all cameras have a single colour image sensor and the layout of light detectors is unknown.
Sensor image size in MP
The sensor image size in MP is a metric used to indicate the potential actual resolution of a generated image. A greater resolution usually translates into more detail that can be captured. Unfortunately, a greater resolution reduces the amount of useful light that falls on each cell that is part of the sensor, leading to a poorer end image. This is the reason why sensors have a set resolution and, on a specific decade, the performance is relatively limited, as developing a sensor with better sensitivity and greater resolution is no easy task.
It is essential to note that professional equipment specifications is accurate while consumer devices, such as smartphones, can have unrealistic claims of such performance fueled by marketing goals. However, even in this case, it is important to know that the sensor image size is less important than sensor's physical size, as the surface are exposed to light is the single most important factor in determining the potential capability of a camera. This surface needs to be as large as possible to capture light in a split second and there is no reliable way to compensate for a small sensor.
The advertised value of a phone camera's image sensor has steadily evolved into a marketing information that has, unfortunately, much less relevance than it had in the past. Before the advent of advanced image processing, this value was almost always the native capability of the image sensor inside a camera. As development of new sensors with higher density, able to capture higher resolution areas at the same size hit a technology limit around 10 years ago, manufacturers turned to image processing and algorithms to boost the perceived resolution, which has nothing to do with the actual capability of a sensor.
In actual terms, a phone sensor could present a 10-25MP value, while the advertised value can reach 100 or 200MP