An image sensor is a device that converts an optical image to an electric signal
The sensor builds a image out of dots called pixels , the more pixels your sensor has will affect the image quality of your prints depending on how big your final image will be
The importance of sensor size
I like how he explained the advantages of a full frame sensor and
the advantages of a cropped sensor
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| ^ less pixels ^ less detail ^ ^ more pixels ^more detail ^ |
The more pixels the more detail in the picture , as pixels decrease the less detail
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| 1st image is 72-ppi 2nd is at 300 -ppi |
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| CMOS SENSOR |
CCD sensor
Relationship Between the Number of Pixels on the Sensor and in the Digital Image
Normally each pixel in the digital image is based on the measurement in one square pixel so a 10 megapixal image is based on a 10 pixel measurements
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How a pixel gets its colour |
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some canon cameras use that use a aps-c sized sensor which is smaller than full-frame. when you put a lens on the camera, the smaller sensor can only see a cropped portion of the entire picture. mathematically, the crop factor on most canon cameras is 1.6x.
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My canon 450 d has a 1.6x sensor
Because the sensor is smaller than a full frame sensor
A 100mm lens would show a area of view that a 160mm lens would show on a full frame sensor
Multiply a lens focal lenght by 1.6 to get the focal lenght of a lens you use
I have noticed the disavanges of a croped sensors praticly with landscape photography and articurral lanscapes
With my macro and sports photography it has been a advanging in getting even closer to the subject so i have been able to get closer then a full frame sensor with same lens .
The crop sensor's photo would be more magnified than the image captured by the full frame camera but the quality of a full sensor performer better in low light
A larger image sensor will produce a better image than a crop sensor because the pixels will be larger .
so if you have the budget a full frame sensor will produce a betetr quaity of image .
conclusion
A sensor is the one of the most important parts of a camera
The better the sensor, the more faithful the reproduction of the scene you want to capture
