csoars said: Stick film between heavy books to make as flat as possible, leave scanner sharpening at zero, add lots in post. In Lightroom I usually add 70 as the amount abs then use masking to tone down exaggerated grain.
gancsos said: Some scanners have little “feet” that go into the bottom of the neg holder. They differ in height by like +/- 1mm. Some have different ways of inserting the feet to vary the height of the carrier. Do test scans for best position.