iSRD makes scans worse

[JoGre]

When I switch in the iSRD my scans look like this:



What could be the cause?

Thanks in advance.

[LSI_Ketelhohn]

Dear customer,

At a first glance it looks like the infrared channel of your scanner is not working correctly.
Please check the infrared image.
To do so first activate the 1:1/HQ mode.
Then hold the following keys while clicking on the main preview.
Windows: <shift> and <Ctrl>
Mac: <shift> and <command>

The image will change to a B&W representation of the infrared channel.
It should only show dust and scratches as dark areas. No image or other structures should be visible.

Kind regards,
Arne Ketelhohn.