For what its worth, first impressions sometimes are wrong. Last week I praised the 4990 and my initial impression was that it was superior to the Microtek 1800f. Upon further analysis I find that I was considerably mistaken. The 4990 produces very sharp scans, perhaps a tad sharper than the Microtek, but it is significantly inferior in dmax. Part of the problem in my first impression is that I was using the native software of the Microtek, for whatever reason, could be error operator, the native software is not as good as Lasersoft Ai. This weekend I installed Lasersoft, which comes standard witht he 1800f and the scan quality doubled in quality and comparing the 4990 and the 1800f but with Lasersoft, the 1800f produces much more shadow detail, richer and deeper colors and better color fidelity. Another problem in my use of the 1800f is that I had the scanner on top of a file cabinet that evidently was not sufficiently stable. So the vibration produced by 100mb scans introduced enough movement to make the scans soft. Placing the scanner on the floor considerably improved the scan sharpness. The moral of the story: new technology is hardly plug and play and there are so many variables that novices like myself can easily overlook. Many of the varialbes are never discussed on the internet and you just have to slug alone with trial and error. Bottom line: because I shot mostly slide film the Microtek stays and the Epson goes back to the store.