Sensor Size is directly related to Crop Factor. Sensor Size plays a very important role in clicking the images
There are various type of Sensor Size are as follows :-
1). Full Frame (36mmx24mm) – This is the largest sensor type it is equal to 35mm film. Full Frame sensor are 2x the largest than APS-C type Sensor. Due to its larger size it covers the more area across the field. Full Frame sensor got a No Crop Factor, and generally the lenses manufactured are special design for full frame DSLR body. Full Frame DSLR body with wide aperture give Maximum Shallow Depth of Field. In Nikon DSLR it denoted by FX at the coner of Body.
2). APS-H (28.7mmx19mm) varies from brand to brand – APS-H means Advance Photo System. This Sensor type is smaller than Full Frame body. It is most popular sensor among interchangeable camera and ponsumers camera this APS-H got a 1.2x or 1.3x(for different brand). Lenses design are different from full frame body.
*** Lenses designed for Full Frame body can be fixed in APS-H or APS-C sensor but, APS-H or APS-C Lens can’t be fixed over Full Frame.
3). APS-C (23.6mmx15.8mm) – This sensor type is also very popular among Interchangeable camera’s the camera manufacturer use different crop factor e.g Canon APS-C crop factor is 1.7x where as Nikon APS-C crop factor is 1.6x.
4). Four Thirds (17.3mmx13mm) – Approx it is Quater of size of Full frame sensor. This sensor type is created by Olympus, Panasonis, Fuiji Camera manufacturer it has a 2x crop factor which double the focal length.
CX format (1 inch or 13.2mmx8mm) – This was announced in 2011. It is adpoted in Nikon 1 Camera System. This CX has a 2.7x Crop Factor.
Other Smaller sensor type are :- 1/1.7 inch, 1/2.5 inch.
***Crop Factor – It describe the differnce between your camera and sensor size. It is basically the image crop by sensor when fixed over full frame body or 35mm e.g APS-C has crop factor of 1.6x means that it crop image by 1.6x there is another facotr act that is increase focal length e.g if you fixed 200mm lena over APS-C body the focal length after full zoom will be (200mm X 1.6) gives 320mm. This resultant 320mm is the equivalent focal length which means when you fit 320mm lens on full frame or 35mm to get the same field of view.
More the Crop Factor more the zooming effect.
How to Calculate Crop Factor :-
To calculate crop factor it is necessary to use Pythogorous Theo.. a2 + b2 = c2, And Square root of resultant number.
Image Source : Canon, Wikipedia.