UMAX Technologies Astra MX3 Owner's Manual page 27

B/W Photo - Scans black-and-white photos using 256 shades of gray (ranging
from white to black) so you get smooth shade transitions in your scanned
image.
B/W Photo, 14-bit- Scans a black-and-white photo using 14-bits of data to
define each pixel. This setting produces more gray shade accuracy than the
B/W Photo option, but also produces larger file sizes.
B/W Document - Scans text documents, black-and-white line art, and other
black-and-white documents. This selection creates the smallest file sizes.
FAX - Scans at the appropriate resolution for faxing.
OCR - Scans at the appropriate settings for optimal OCR recognition.
Note: Not all graphic applications support 42-bit graphic files. To determine
whether the software you want to use is capable of working with 42-bit
graphics, refer to your software documentation.
Changing the Resolution Setting
Scanning resolution is measured in dots per inch (DPI). Resolution determines
the amount of information the scanner will capture in a scanned image. The
higher the resolution, the finer the image detail, and the larger the file sizes.
VistaScan lets you choose from the following resolution settings:
25-2400 dpi
Higher - This option opens a pop-up menu that contains higher resolution
settings from 3600-9600 dpi.
Custom - This option opens a slider control where you can set any
resolution up to 9600 dpi. Click and drag on the slider to change the
setting and click on the OK button.
The following table gives you an idea of the file sizes you can expect based on
the original image size and the resolution setting you specify. These values are
based on scanning images in 24-bit, True Color RGB mode. Image sizes
shown below are given in megabytes.
UMAX Astra MX3 Owner's Guide
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