LaserSoft Imaging

I use the latest version of Silverfast SE
My OS is Windows 10
Scanner is CanoScan 9000F MarkII

After I've done the final scan and then watch the picture using Windows picture viewer or Irfanview, the picture are unsharp.
The left side of the attached picture is in preview and the right is how the final scan look.
I've tried a lot of different settings but nothing change. I don't know if I have missed any settings but can't find any.
I also attach a screenshot of my settings.
I would be grateful for any help in this matter.

Dear customer,

Have you tried using a higher resolution?
This devices uses a fix focus system so it's sharpness can not vary.
The preview however might use a higher resolution then your final image.
Additional software sharpening is available through the USM tool.

Kind regards,
Arne

Thank you for your reply.
The maximum resolution I can select from the predefined options is 600dpi. I have tried that and it gives the same result.
I was suggested to try in 9600dpi and 100% zoom but that gives a filesize of 2.86GB.

I'm pretty new to this so maybe I am missing something?

The slider sets the scan resolution. The preset the internal base/display/print resolution for calculating the displayed image size.
The slider should stop at various steps. These are the resolutions the scanner offers.
9600 is rather high and should only be used if you intend to print a very large size. Most film material offers about 3000 to 3600 ppi.

Kind regards,
Arne