Igor, I just got back to this task again.

My problem was that our DR5020 scanner would switch to simplex mode, or that it would scan duplex but both sides would come out as all black. I thought it was an auto-contrast or auto-brightness problem.

I accidentally found out that if I invoked the ShowScanPreferences method in the Kodak Pro (now and eiStream Kofax product) ActiveX control, I could choose the kind of output image I wanted in a dialog instead of having to know the obscure constant to feed to the scanner part of the ActiveX object. When I picked the type I really wanted, which was "Smallest size" and TIFF, voila, it worked.

This led me to the realization that it wasn't the scanner settings at all, but the image type that was (mis)controlling the scanner -- somehow I was asking for an "impossible" type of output, and the result was setting the scanner to produce this output... Am I making any sense?

So, once I had the right image output type, I found out what THAT was by setting it in the ShowScanPreferences dialogue and then querying the value of the GetPageTypeCompressionInfo. Now that I know that, I can feed it to the SetPageTypeCompressionInfo and not have my users see the ShowScanPreferences dialogue.

Hope this helps someone else struggling with the complexity of TWAIN/ISIS control!

Kevin