UMAX Technologies Astra 2000U Owner's Manual page 46

Using Custom Resolution Settings
You can also specify custom resolution settings that you can use
when you scan. The maximum custom resolution setting you can
define is 2400 dpi. To define the custom resolution settings:
1.
Choose the Custom... option from the Resolution drop down
menu. The Custom Resolution window opens.
2.
Enter the desired resolution setting (between 50 and 2400 dpi)
in the Custom resolution #1 text box.
3.
Repeat step 2 to define the Custom resolution #2 and Custom
resolution #3 settings.
4.
Click OK. The settings you defined appear on the Resolution
setting drop down menu, under the Custom heading.
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