4. Image Operation
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4.1 Why does multiple rotating or deskewing distort the scan?
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When rotating or straightening an image, BCS-2 changes the position of the pixels within the image. This is done either on the basis of a specified or an automatically calculated angle. The software first tries to determine the best way to improve the image. The correction angle is also calculated for automatic straightening. Once the method and angle are determined, BCS-2 deskwes the image.

Both functions influence the quality of the image of an image, since they leave traces in the image (e.g. stair formation) with every use. A larger rotation angle usually gives a better result than a smaller one. If these functions are executed multiple times, the correction angle becomes smaller with each repetition and the blurriness thus becomes larger. They should therefore only be executed once on an image if possible. If automatic deskewing or rotation does not produce the desired result, use manual deskewing.

4.2 Why Does BCS-2 Display 32-bit Colour Depth for All Colour Images, even if They Are 24-bit Colour Depth Images?
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BCS-2 stores all images with 32-bit colour depth, regardless of whether 24-bit or 32-bit images are delivered. When the images are transferred, they are converted back into images with 24-bit colour depth. The 32-bit colour depth is distributed as follows: 8 bits for each colour channel (RGB) plus 8 bits for the alpha channel. In the BCS-2 context, QT appends the alpha channel and thus the additional 8 bits of colour depth to the image.

4.3 Why does BCS-2 sometimes save bitonal tiffs as greyscale tiffs?
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BCS-2 always saves bitonal images in “greyscale” format if the “Increase/decrease contrast” function is used when editing images in BCS-2. There is no such function for bitonal images. As a workaround, we recommend first using the “Increase/decrease contrast” function and only activating binarisation immediately before transferring the job.