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Sensor and Lens

 List of Resolutions

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Sensor and Lens

 List of Resolutions

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Sensor and Lens

 List of Resolutions

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In the List of Resolutions box of the Sensor and Lens panel, you can specify a list of possible resolutions of the active camera in pixels.

If the list of resolutions is set, then only resolutions from the list will be shown in the drop-down list of the Active pixels combobox in the Camera Geometry box.

 

In the list, you can set the Crop factor for each resolution value. In this case, when choosing a resolution from the list, the corresponding Crop is assigned to the camera. Thus, it is possible to significantly improve accuracy of modeling cameras, which size of active area of the image sensor depends on resolution.

 

See more Specifying active area size of the image sensor

 

If the List / Range and List of Resolutions strings are specified in the camera model parameters, the user only needs to select the lens focal length and resolution from the drop-down lists to obtain accurate model of camera's view area, taking into account  lens distortion and dependence of active area size of the image sensor from the resolution.

 


 

The List of Resolutions is a list of substrings separated by semicolons:

 

H1 * P1 | C1; H2 * V2 | C2; ... ... Hn * Vn | Cn;

 

Each substring corresponds to one of the possible resolutions and consists of the numbers of pixels divided by asterisk and the Crop factor, separated by vertical bar:

 

Hn - the number of active pixels horizontally;

Vn - the number of active pixels vertically;

Cn - Crop. If Crop = 1, then it can be omitted.

 

List of Resolutions can contain no more than 200 characters.

 

Examples:

 

1920*1080;1280*720; - the camera has 2 possible resolutions 1920*1080 and 1280*720.  The size of active area of the image sensor does not depend on the resolution..

 

1920*1080;1280*720|0.67; - the camera has 2 possible resolutions of 1920 * 1080 and 1280 * 720. With a resolution of 1280 * 720, the size of active area of the image sensor decreases in 0.67 times.

 

The List of resolutions is included in the list of camera model parameters and can be automatically assigned to the active camera when it is assigned a model from the Table of Camera Models.

 

 

 

The List of Resolution string can be edited as plain text or using the drop-down form, which can be opened by the button in the upper corner of the List of Resolution box.

 

On the form select or enter the required number of pixels and click Add. The string will be automatically formed in the top box of the form.

 

To record the string to the List of Resolution box, click Record.

 

Clear clears the top box of the form.

 

Cancel closes the form without recording the string.

 

For reference, the Aspect ratio is displayed as an ratio of the numbers of pixels, as well as the resolution in megapixels.

 

If you click the Crops > Calculate button, then the crop factors for the resolutions in the list will be calculated automatically. Resolutions with the maximum number of pixels horizontally or vertically will be assigned crop = 1. Lower resolutions will be assigned crop factors less than one.

 

Automatic calculation of crop factors will be correct if the conditions are met:

 

The list contains the maximum resolution of this image sensor horizontally and vertically.
The camera generates images with lower resolutions using a smaller number of pixels of the image sensor, rather than resizes the image with the full number of pixels of the sensor. If for obtaining lower resolutions the camera uses all pixels of the image sensor, then the crop of all resolutions must be equal to one or absent (the cropping equal to one can be omitted).

 

Crop> Delete button removes Crop factors, that is, makes the size of the active area of ​​the image sensor independent of resolution.