I have a Viisan A3 scanner and every time I scan a print I get faint bands across the print but mostly in the dark areas. The attached example shows the bands on the man's shirt. They are not as noticeable on the lighter skin areas but can be seen sometimes. I expect it's nothing to do with the print itself as the blank area under the print which the scanner included also shows the problem.
That looks like a hardware issue for sure. I'd contact the seller or manufacturer.
First thing that comes to mind is an anomaly in the sensor, given how sharply it cuts off. Sensors like these may consist of a number of separate sensors glued together and it's conceivable one of them happens to not be performing on-spec in this array. That's just thinking out loud though.
In terms of trying things that may or may not help - carefully clean the entire platen, especially the edges. On transparency scanners (I'm aware you're scanning prints here), the first strip of the glass is often used by the scanner as a calibration area. If there's any dust etc. there, it'll produce a longitudinal band. There's a very slight chance something like this is happening in your device. But it's a long shot, really. I think it's more likely this is something that'll require a hardware fix/ replacement.
What software are you using with the scanner? Looking at the beard it seems like the negative could possibly be under exposed, in which case it may be having a hard time resolving the blacks because there is no full contrast range to calibrate with. You could try it with Vuescan as a comparison or find a different scene to compare with, does a landscape for example still show the banding?
What software are you using with the scanner? Looking at the beard it seems like the negative could possibly be under exposed, in which case it may be having a hard time resolving the blacks because there is no full contrast range to calibrate with. You could try it with Vuescan as a comparison or find a different scene to compare with, does a landscape for example still show the banding?
That's certainly true, but I'm willing to take @thefizz's question at face value and assume that the artefact that he gets in the scan is not there on the print. That would isolate the problem in the scanning process.