Keep Proportion - Microtek ScanMaker 6100 Pro User Manual

If you know the exact input size for your image, or if you wish to
"lock" the settings of your scan frame to a particular size, enter the
Scan Frame width and height values first, then check Fixed Scan
Frame. Your scan frame will be fixed at those values. So even if you
move the scan frame around the preview image, the dimensions of
the frame itself will remain unchanged.
Fixed Output Size
When the Fixed Output Size option is checked, the values specified
for output width and height remain fixed. If any of the input values
are changed, the scaling will be automatically adjusted
proportionally to maintain the output dimensions as defined.
If you know the exact output size for your image, enter the output
width and height values first, then check Fixed Output Size. The
image will then be scanned and output at the values specified.

Keep Proportion

When the Keep Proportion option is checked, the width and height
values of the image are kept in proportion despite changes made to
either setting. This preserves the aspect ratio of the image.
This option is automatically checked when either "Fixed Scan
Frame" or "Fixed Output Size" is selected.
Flip/Transform
The Flip/Transform button allows you to rotate and/or flip the
image at increments of 90 degrees.
The effects of the Flip/Transform button are seen only after you
click the Scan button and scan the image. The effects are not shown
in the Preview or Overview modes.
To use the Flip/Transform command,