Below is a video for scanning. Remember that this clip shows scanning at a resolution lower than 300 dpi. If you want to scan photos for print work remember to use 300 dpi for the resolution and scale with the scanner not Photoshop.
Here is a second video showing the descreening options in the Epson Scan software.
Below is a scanned image of material that was offset printed. (scan from a magazine) without using the Descreening feature. It displays obvious moire patterns that become even more apparent on printed material. The Descreeneing feature should never be used on actual photographs or film.
Then next image was scanned using the Descreening feature and can be used for comparative analysis. Both photos are a cropped section of original image. The image below does not contain the sharpness in detail and seems a bit blurry, but it is also missing are the moire patterns.