Optimizing the dynamic range of the scan

Keep in mind that the human eye can detect a wider tonal range than can be printed. If your scanner allows, set the black and white points before scanning a file to produce the best tonal range and capture the widest dynamic range. Then use Photoshop Elements's color adjustment tools to set the white and black points for the scanned image. (See  Adjusting tonal range.)

Getting Images into Photoshop Elements > Scanning images > Optimizing the dynamic range of the scan