The transfer mode that must be used for acquiring images.
Remarks
Native transfer mode is the fast and simple transfer mode and it's supported by any device.
Memory transfer mode should be used if it's necessary to scan high quality images (16-bit grayscale or 48-bit color images) or it's necessary to scan large images with high Device_ImageResolution (more than 300 dpi). This transfer mode is supported by any device.
File transfer mode can be useful with high speed scanners. Scanned images will be saved directly to a disk without any memory operations. Not all devices support this transfer mode.