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Image sensor calculator

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Image sensor calculator

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Image sensor calculator

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Camera Geometry

Sensor and Lens

Calculator

Click to expand

 

The Calculator is intended for convenient calculation :

•Aspect Ratio of Image sensor;
•Aspect Ratio of active area of Image sensor (=Aspect ratio of the output image);
•Crop-factor.

 

About use of the calculator, see: Specifying active area size of the image sensor/

 

The calculator can be invoked by the Image sensor calculator button in the Sensor and Lens box.

 

The calculator consists from the three lines:

 

       Image sensor

 

As a result of click on the left button numbers of pixels of image sensor horizontally and vertically are copied  from the Sensitivity and resolution window to the Hor. and Vert. boxes. If the numbers are not specified, the left button is not available.

To the Hor. and Vert. boxes you can type any values.

 

In the Aspect ratio box the calculated ratio of horizontal to vertical numbers of pixels of the Image sensor will be displayed.

 

Attention! To calculate the Aspect ratio of Image sensor you must divide maximum number of horizontal pixels to the maximum number of vertical pixels in all possible modes of the camera. In general, the maximum number of pixels may be different from those specified in the Sensitivity and Resolution window..

 

For example, a camera has the following resolution modes

1920 x 1080, 1280 x 720, 640 x 360, 320 x 180, 160 x 90

1600 x 1200, 1280 x 960, 800 x 600, 640 x 480, 400 x 300, 320 x 240, 160 x120

 

The maximum horizontal number of pixels - 1920, The maximum vertical number of pixels - 1200. Probable Aspect ratio of the image sensor 1920/1200=1,6=16:10

Clicking the right button the calculated aspect ratio of image sensor will be copied to the Aspect ratio box in the Sensor and Lens box.

 

       Image sensor's active area

 

As a result of click on the left button numbers of pixels of output image horizontally and vertically are copied  from the Processing tab of the Image parameter panel to the Hor. and Vert. boxes. If the numbers are not specified, the left button is not available.

To the Hor. and Vert. boxes you can type any values.

 

In the Aspect ratio box the calculated ratio of horizontal to vertical numbers of pixels of the output image will be displayed.

Clicking the right button the calculated aspect ratio of the output image will be copied to the Aspect ratio box in the Camera Geometry box.

 

       Crop

 

The Crop factor value is calculated from the Aspect ratio of the Image sensor and Aspect ratio of the output image.

 

Attention! The calculated value of Crop has sense only if the active area on the image sensor does not touch the edges of the image sensor. Otherwise Crop = 1 and the result of calculation does not matter.

 

See more: Specifying the crop factor

 

To be able to calculate Crop it is necessary that numbers of pixels of image sensor  are greater than or equal to the numbers in pixels of the active area. Otherwise, the Crop box displays Error.

Clicking the right button the calculated Crop factor will be copied to the Crop box of the Sensor and Lens box.