I actually asked somebody else’s question on the technology forum I’m using SCAN ACE and I’ve had beautiful results most of the time and I’ve been doing this since 2017. This keeps me from having to take my laptop and a portable scanner with me everywhere which doesn’t seem practical to me either way my SCAN ACE was working beautifully now all of a sudden it starts making very light scans. I tried with the camera flash on with the camera flash off in different areas, but on the sides, it would bleed it would fade out on the sides and then I would
adjust the black white ratio and get it halfway decent, but it still started looking awful. Here is a picture. This is how it looks before I adjust the black white ratio, but even then it does not look good. It shouldn’t look like this at all.
This looks like it could be a calibration or scanner sensor issue rather than just the black/white ratio. I would first clean the scanner glass/rollers really well, then run the scanner calibration through Scan Ace if that option is available. After that, test with auto-enhance/auto-contrast/background removal turned off and scan in 300 dpi black & white or grayscale.
If the fading on the sides continues after cleaning and calibration, it may be the internal scan head/light starting to fail, especially since it was working fine before and changed suddenly. I’d also try a different USB cord/port and reinstall the Scan Ace driver/software before replacing anything.