Acer ScanWit 2740S - Scan Quality

All results are based on my own visual evaluations, i.e., I did no measurements here.

In general, the Acer ScanWit 2740S scan quality is okay for the money that it costs. You might hardly get a better quality by a cheaper scanner than this.
While uncritical, normal exposed images are fine, the film scanner has some problems with under-exposed and low key images.

In summary, the Acer ScanWit 2740S is a fair entry-level film scanner for putting some family photos into the computer. However, it is no useful for high-end quality scans especially of difficult samples.

+	Scans with acceptable quality can be made without large manual work.
+	Scan resolutions up to 2700 dpi are feasible. The sharpness of the scans is good.
+	The ScanWit 2740S scanner default settings lead often to the best scan results.
±	The color reproduction is normally okay. But, there is some weakness in the green and brown tones.
±	The color zero calibration is sufficient for a quick scan but not good, i.e., there is often a need to correct the green shadows by a value around 5 after the scan.
±	The practical available density range is sufficient for uncritical normal-exposed photos. But some slides may cause quality losses. Furthermore, the scanner has no lamp intensity control.
±	The "ICE" works fine normally. However, it makes the scans slower and has unexpected limitations.
±	The reproducibility of the scan results is normally sufficient. But, under-exposed or critical images vary.
±	As it is normally absolutely no problem, the single photo diodes and limitations of the optical system may become visible in very critical images.
÷	The scan quality seems not to profit from image scan corrections after the preview. Even a large image-specific gamma correction of 4.0 or above during scan-time for an under-exposed slide seems not to improve the result.
÷	The try to correct the minimum and maximum image-specific settings at scan time leads to heavy damages in the shadows and the lights. Although some more of the possible 256 values per color will be lost, this must be done after scanning for the Acer scanner!
÷	There seems not to be any visible image quality improvement when the "High Quality 48 bit" mode is used. Furthermore, no clue has been found that the scanner should really work with 36 bit color depth internally.
÷	The scanner has no multi-scan feature in order to reduce the noise and there is no grain reduction system.