I recently switched from my Epson and Coolscan to an IQsmart 2. I noticed that when I opened the scanned images in Photoshop they appeared somewhat grainy and exhibited moire on screen. But as I zoomed in, the graininess eventually disappeared and the printed images looked great.

At first I thought that there might be something different about how the IQsmart software was storing the files, but then I remembered that I had upgraded to the latest PS version just before switching to the IQsmart, so I started to suspect a PS problem. I was eventually able to figure out that the default setting for Cache Levels (Edit>Preferences>Performance) was lower than what it had been in the previous version. After raising the number everything looked fine on screen.

I'm just posting this for information in case someone else encounters the same problem.