Flat bed scanners capture a whole line of the film at a time, this makes the quite fast but it also means that lens based aberrations can be introduced. This is normally evidenced by colour separations along contrasty edges but can also show as variable colour on textures (see the image above which is a photograph of sea waves at sunset. The colour should be consistent across the scene but the Imacon shows variable colour).
After testing various scanners in our research we have seen this effect to some extent or other in every Imacon scanner we have seen and all flatbeds tested including Fuji Lanovia, Screen Cezanne, Eversmart and Creo and also in consumer scanners such as the Epsons. Some scanners such as the Creo IQSmart and the occasional well maintained Imacon minimise these effects but they are still apparent when comparing side by side with a good drum scan.
Here is another example from an Imacon showing the effect next to a speck of white lichen on dark rocks.