I have DotTwain working fine with single image capture, and the capture of multiple documents into individual images using the document feeder.
I'm struggling with loading multiple sheets into the document feeder and acquiring them as a multi page tiff. I'm finding that when I call acquire, the FileTransfer event is firing as per normal and I'm setting the file name. But then the cancel event is firing straight away, and not a murmur from the scanner.
When I call GetSupportedImageFormats() on the device, it returns Bmp and TiffMulti. Oddly it doesn't list Tiff. Acquisition works fine if I set the device's FileFormat to Tiff, but doesn't work at all if I set it to TiffMulti.
The device is a Brother MFC-7820N connected via USB.
I'm capturing directly to file, if that has any bearing.
If this isn't how one acquires multiple documents into a single multi page tiff, then pointers are appreciated.