Let the User Control the Scanning

You must decide when using AcquireToDoc Method, AcquireToFile Method or AcquireToPage Method whether to set the scanning capabilities in your application or to let the user set them. To let the user set them, simply leave the UseUI Property set to True - this will cause the TWAIN Data Source to display its settings dialog, which will give the user full control over the image acquisition.

If you set UseUI Property to False, you can still set the device capabilities by the SetCapability Method. In that case, the values that you set with SetCapability Method will become the default values in the Data Source's settings dialog.

If you are scanning with AcquireToDoc Method or AcquireToFile Method, and have set UseUI Property to True, be aware that the UI will only appear once, before the first page is scanned. Therefore, the settings that the user makes with the UI will be applied to all of the pages scanned during this scanning session. For this reason, if the images in the multi-page file will require different settings, you will need to use the AcquireToPage Method for each page (changing the capabilities as needed before each call to AcquireToPage Method), and then build an IGDocument Object from the individual IGPage Object.