iSRD corrections seem to be offset

[TMavis]

I'm new to SilverFast so I hope this topic isn't obvious. I did search but perhaps I searched wrong.

My understanding is iSRD is used to remove dust and scratches. Seems to do a good job. However, every couple frames it seems to be offset. See picture example.

Keil Christmas 1997 4.jpg (97.45 KiB) Viewed 3350 times

Any ideas of why this is happening? I'm scanning 35mm negatives from 80s. Kodak Gold Max 400.

Also, my understanding is SRDx also removes dust and scratches. However, SRDx does not appear to do anything.

[LSI_Ketelhohn]

Dear user

This can happen when the RGB and infrared images are not properly aligned.
Try adjusting the offset slider for iSRD in the preferences' special tab.

Kind regards,
Arne