Hugin Camera and Lens tab

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Radial Distortion, Image Center Shift and Image Shearing






Exposure and Color

Exposure (EV), EV stands for Exposure Value, setting it to 0 (zero) will result in hugin applying no exposure change to the photo.


Very often, different photos in the same project, even those with the same lens number, will require a different Exposure. This could be because the photos were taken with a different shutter-speed or simply because the light changed between shots, if so uncheck Link here before optimising exposure in the hugin Exposure tab.

The Red multiplier and Blue multiplier settings are used to account for changes in white balance (also known as colour balance or colour temperature) between photos. Setting them both to 1 will result in no white balance change (the numbers are relative to the green channel which stays unaltered).

As with exposure, different photos in the same project are quite likely to require different white balance. Typically this will be caused by variations in lighting conditions between shots - For example a cloudy scene will contain considerably less red light than the same scene under direct sunlight, so uncheck Link here before optimising White balance in the hugin Exposure tab.


Vignetting is dependent mainly on your lens and the aperture. Usually the centre of the image is brighter with a falloff towards the edges. The three numbers here represent a polynomial curve used by hugin to correct vignetting.

You are not expected to guess these values, they are generally loaded with a lens profile or calculated from two or more overlapping photos in the hugin Exposure tab.

Set the values to 0,0,0 for no vignetting correction.

Usually all photos taken with the same lens will have the same vignetting, keep Link checked to ensure hugin applies the same vignetting correction to all photos with the selected lens number.

Vignetting Center Shift

The centre of vignetting is rarely the exact centre of the photo. The two numbers here indicate the position of the vignetting centre. The scale is in pixels, with 0,0 indicating the centre of the photo. The values are independent of the d & e parameters which specify the origin for projection and geometric distortion.

As with other lens parameters, this Vignetting Center Shift can be optimised in the hugin Exposure tab. Keep Link checked to ensure hugin applies the same vignetting centre to all photos with the selected lens number.

Camera Response

The camera response curve is used both for mapping the images to a linear colourspace when creating HDR output, and for normalising the colourspace for internal vignetting, brightness and colour corrections when creating 'normal' LDR output.

hugin uses the EMoR response model from the Computer Vision Lab at Columbia University which simplifies the full response curve to these five empirical coefficient numbers. You are not expected to guess these values, they are generally loaded with a lens profile or calculated from two or more overlapping photos in the hugin Exposure tab.

Set the five numbers to 0,0,0,0,0 to use a generic response curve or change the Type to Linear to indicate that your input photos have a scene-referred or HDR response.

Keep Link checked to ensure hugin applies the same response curve to all photos with the selected lens number.