UMAX Technologies Astra 3400, 3450 Resolution/File-Size Guidelines, Recommended Resolutions

The table below 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.

Table 1. Resolution/File-Size Guidelines

Resolution			Image Size
(dots per inch)	Image Size 4x5	Image Size 5x7	8.5x11
72	0.30	0.53	1.39
100	0.58	1.00	2.68
200	2.29	4.01	10.70
300	5.15	9.01	24.10
400	9.16	16.00	42.80
600	20.60	36.10	96.30
800	36.60	64.10	171.20
1200	82.40	144.20	385.20

NOTE: Choosing the True Color RGB 42-bit setting captures more data than the 24-bit setting. This means that the file sizes listed above will be larger if you scanned images using the True Color 42-bit RGB setting.

Choosing the Best Resolution for Your Scanning Project

To choose the best resolution for scanning, determine what you are going to do with the image once it is scanned. Matching your scanning resolution to the image use will give you the best image for that purpose and will keep the file sizes to the minimum needed.

Table 2. Recommended Resolutions

Image Use	Recommended Resolution
Printing	300 - 600*
Viewing on the Screen	72
Viewing on the Web	72
OCR, B/W	300
Pre-Press	600
Enlarging or Reducing	600

*Depending on the resolution of your printer

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.

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